BORIS Johnson is a “nasty piece of work,” who will be stopped from delivering the Brexit he wants by a progressive alliance of MPs, Sir Ed Davey, has suggested.

In an exclusive interview with The Herald, the contender for the Liberal Democrat leadership, who is challenging favourite Jo Swinson for the party crown, says he can overturn the odds come Monday afternoon and predicts the result of the ballot of 107,000 party members will be “very, very close”.

The 53-year-old London MP fears that a Johnson premiership will be harmful to maintaining the Union.

Asked if the Tory frontrunner’s victory in his party’s leadership race would threaten the United Kingdom and send the wrong message to Scotland, Sir Ed replies: “Boris sends the wrong message to almost every person I know; Scottish or not Scottish. He is unhelpful on every issue I can imagine. It doesn’t help those of us who believe in the United Kingdom, who believe in progressive liberalism.

“To some of those who paint him as liberal I say: have you heard what he has been saying throughout his political career? He has been anti-Scottish, anti-gay, anti-Muslim. He has said some most unpleasant things not just once but several times. People like to laugh him off. Some say he makes people happy, he’s a character, he’s a card; he is a nasty piece of work.”

He goes on: “A week is a long time in politics and I’m not convinced yet Boris will be PM at the end of the year. I’m not convinced yet that Brexit will happen. One needs to be a little more strategic in one’s analysis here. I am fighting to stop Johnson. I am fighting to stop what he stands for; that it is Brexit that is dividing our country.

“He could become the PM but he is not there for life; he may not be there for very long and he may not be able to deliver Brexit as he promised. When he fails – I’m delighted Parliament has passed the measure[on trying to block Mr Johnson from suspending the Commons to push through a no-deal Brexit] – and we stop him, he will get torn limb from limb by his own side.”

The former Cabinet minister insists a no-deal Brexit is a misnomer and if Britain crashed out of the EU, Mr Johnson would not secure a “Trumpian nirvana” but from day one would have to negotiate with Brussels.

“Johnson or whoever would be, frankly, on their knees. We would have irritated 27 of our allies and I don’t believe Johnson has the negotiating skills to find his way out of a paper bag, let alone negotiate with 27 far more experienced people.”

Sir Ed notes how the EU would strike a hard bargain and that the £39 billion divorce bill would go up to £50bn because Brussels would say: “’If you want to talk about a trade deal…we’re not paying the cost, you’re paying the cost because you’re the one with no-deal.’”

He explains: “The sheer obvious reality to anyone who has negotiated in politics and business is that no-deal will mean deals and they will be done from the weakest imaginable position. Some of us have led EU negotiations…and the way you do them is you build relationships, you get to know your friends and you understand your competitors and why they don’t feel the way you do; you put yourself in their shoes, you are friendly to them and you find a way forward.

“You do not shout from the white cliffs of Dover and you are not rude. It’s the worst imaginable type of negotiations. I worry immensely about this situation because he just doesn’t get it.”

Sir Ed, who as the Coalition Government’s Energy and Climate Change Secretary, spent many days and weeks negotiating deals with the EU, stressed that people did not understand how the relationship worked.

“Europe does not tell us what to do. We tell Europe what to do. Bizarrely enough, when you do proper politics and engage and build relations, it’s Britain maximising its influence on a dramatic scale. That story isn’t told,” he declares.

“I have heard people say we’re being bossed around by Europe. Think what’s happened. This is not Germany in some sort of new Third Reich or Fourth Reich. Germany is nowhere near as strong people think it is but wants to work with its partners to make sure a Fourth Reich never happens.

“The concern isn’t about Germany bossing Europe, the concern ought to be about Vladimir Putin and the real tension in the world between the US and China…

“The idea that Europe is a threat to us, it’s just the reverse. With our European friends, we can exert influence and prevent conflict.”

The Lib Dem leadership contender noted: “One thing about the referendum is that people understand Northern Ireland in a way they didn’t before. Some 3,600 people of our own country were killed by guns and bombs and that peace is underwritten thanks to the EU and the freedom of labour, which enables the Irish Republicans to think they have an island of Ireland in effect and the Loyalists to think they are part of the UK.

“It’s the best compromise ever produced for peace. Everyone got what they wanted because of the single market or pretty close,” he insists.

Asked if a Johnson premiership would result in a Trumpian Britain, the Lib Dems’ home affairs spokesman, says: “There is a huge danger…The current parliament wouldn’t allow him to go down a Trump route.

“But if he was to get a big majority[at an election] post a Brexit deal…I’m sure he and his backers will be looking for a sort of North American-style Britain; very low regulation, cut taxes, reduce the welfare state.

“In that situation, do not be poor, do not be middle class; if you’re not super-wealthy, you are in trouble. Some of us reject that for Britain because we want to look after the poor, the vulnerable, the disabled, the sick in the way they are not looked after in many parts of America, and would be suggesting we looked at the Nordic countries and the Scandinavian model.

“Why couldn’t we talk about a public service that is modelled on big investment even if it would mean higher taxes? The British people would prefer to have that type of European model than the North American one.

“People don’t understand how the homeless are treated in the States, how the disabled are treated. In large parts of America, they are left to rot; literally rot. I don’t think people want that.”

Sir Ed argues that what Trump is doing to America by playing the race card is “divisive, it’s nasty, it changes the whole mood of the nation”. He says a great nation like the US has in many areas helped on diversity and has been ahead of the UK with some excellent laws but at present the country is “going backwards”.

Earlier this week, the Lib Dem leadership contender’s former colleague, Sir Nick Clegg appeared to almost admit the Union was lost because of what he described as the “Brexit demon”. The ex-Deputy Prime Minister claimed the break-up of Britain was now “more likely than not”.

While Sir Ed agrees Brexit is a “demon” and that if it happens, it would create “deeper divisions than people are expecting,” the MP for Kingston and Surbiton disagrees with his friend.

“No, I wouldn’t say it’s more likely than not. It clearly increases the risk that we could see a divorce but that doesn’t necessarily mean that it will be a divorce and a break-up of the British family because there is still a lot of people who do not like independence in Scotland but the way these different feelings come together there may be some people who are more pro-European than they are pro-British.

“If Brexit happens, the sheer cost, complexity and disruption of breaking a relationship of 50 years might make people think again about breaking a relationship of 300 years,” he argues.

But surely the push from himself and his pro-Remain colleagues simply legitimises the argument for those who want a second attempt at Scottish independence.

“No. For three or four reasons. First of all, to be fair to the SNP in the Scottish referendum, they said what Scottish independence would look like. It was detailed and I wrote some of the alternative positions. No one really in Scotland could say they weren’t told precisely what independence meant or a version of it. They lost by 10 points.

“In the Brexit referendum, the Leavers did not say what Brexit meant. I call it the baked bean referendum because there were 57 varieties of it. If anyone doubts that people did not know what Brexit meant, look at the last three years; Brexiteers have argued among themselves. It’s clear people didn’t know what Brexit meant.

“It was a very different vote with different information and, of course, it was a very narrow vote in the case of the Brexit referendum. So, you are dealing with two very different beasts.”

He repeats the point that if breaking up a union of 50 years is extremely difficult, what would it be like trying to end one that is 300 years old.

“There is only so much damage, disruption, uncertainty and instability people in their lives and businesses and their governments can take.

“When I looked at the case against independence, I tried to be objective but thought: ‘Oh, my god.’ How would we manage Scottish independence?

“I did a lot on energy and the SNP budgets were based on a very high price for oil and it lasting for a long time. The oil price is up a bit but it’s nowhere near where it was and the SNP apparently believe in a climate emergency; the two don’t go together. So, they won’t have any money. There are these inconsistencies in their position. Do they really want to impoverish the whole of Scotland?”

Sir Ed becomes animated when he talks about the “dramatic change in British politics” and how the Tories and Labour are “dramatically split”.

He points to the favourable results for his party in the recent European and English local elections that have boosted its poll ratings to around 20 per cent, meaning that with the Tories, Labour and the Brexit Party, there is now – just like in Scotland - a four-way split in politics south of the border.

The backbencher notes how at the party hustings with Ms Swinson there is talk of the Lib Dems becoming the largest party at Westminster.

But surely it is pie in the sky to think a party with just 12 MPs could jump to over 250?

“It’s so not pie in the sky. We are doing our own internal polling and it’s bearing out what the national polls are bearing out. Between 18 and 23 per cent. There is a four-way split.

“If the Right remains split between the Brexit Party and the Tories, then our ability to come through the middle and get a load more seats in our own right and with a little bit of luck, with some money get a massive load of seats becomes really big because we only need 30 per cent in some seats to win.

“It’s like Scotland…When you have a four-way split, it makes a big difference. That starts going across England if you have a Brexit Party taking over the Tories and so that’s a scenario where it’s very credible to say we could be the largest party. If you get to the late 20s and early 30s and we start winning 200-plus seats. Now, I’m not predicting that, I’m not saying it’s going to happen, I’m just pointing out it is a credible option.”

He says the real challenge for the Lib Dems is if Brexit does not happen, then Mr Farage’s Brexit Party and the Tories could do a deal to form a Leave Alliance.

“Is there a Johnson-Farage handshake and a deal done. That clearly would be challenging because we would have to think hard about going beyond an informal Remain alliance to a more formal one.

“If there was a Leave alliance, I would certainly as leader be willing to stand[the party] down in a number of seats for Remain candidates, where we clearly couldn’t win but our vote could stop a decent Remain Labour MP from winning.”

So, the Remain pact with the Greens and Plaid Cymru that has given his party a clear run at the August 1 Brecon and Radnor by-election could be replicated at general election?

“Yes. I’ve made the condition if there is a Leave alliance. If there is not one and the Right split, then we could come through the middle and be the Remain party, that’s how I read it. There is an opportunity. If the Right is split, we could see a Remain Parliament. But if the Leave alliance happens, it would be incumbent on the Remain candidates of all parties to find a way to get together to stop a Far Right coalition destroying our country.”

But how would that work in Scotland?

“I don’t know,” admits Sir Ed. “It’s a different ball game in Scotland. You have two forms of nationalism coming together; English and Scottish.

“It would be difficult for the Lib Dems to do a deal with the Scottish Nationalists because they don’t just want to oppose Brexit, they want to break up the UK and we are fundamentally against that. So, it’s difficult to see it in Scotland.”

But he then notes, perhaps more in hope than expectation: “One thing you would have to do is nail the SNP to the mast. If they are serious about stopping Brexit, they must be willing to do deals to stop Brexit, which are contingent without anything to do with Scottish independence.”

Already the Lib Dems have seen former Labour and Change UK candidate Chuka Umunna switch to their team. Sir Ed was asked if more will follow?

“Yes.”

He was asked what made him so confident?

“Multiple conversations that I and others have had. I’m not going to say who or when because that would be completely inappropriate. Change UK MPs are thinking. There are at least one or two Tories who are thinking and there may even be still some Labour MPs who are thinking of us.”

He goes on: “There is a chance we might win the Brecon and Radnor by-election; that would give us a boost going into summer. There is a chance in September/October we might get one or more defections, which would give us a boost.

“The challenge for the next leader on the basis of this amazing, game-changing revival in our fortunes over the last three months is can we keep that pumped up and part of that is publicity. We know whoever the leader is, publicity for the Lib Dems is a challenge but that’s part of a leader’s task to get out there and get publicity. But there’s nothing like where people are coming to our banner; that’s the best publicity.”

The former Energy and Climate Change Secretary, who has put “decarbonising capitalism” at the heart of his campaign, has raised eyebrows – not least from his Scottish colleagues – about his proposal to ban internal flights.

But he points out he has been “slightly misreported” and was “absolutely not” saying he wants to ban all domestic flights.

“It would be nigh on impossible to stop a number of flights to Scotland and to Scottish islands for example. But do we think it’s sensible that people fly from Birmingham to London or from Manchester to London? These are flights, if you care about climate change, we should be looking to get rid of.

“I hope that over time we would reduce those domestic flights although there are some I don’t see we will ever get rid of. Until we can have completely clean zero carbon flights – which is possible but isn’t going to happen any time soon – we need to reduce the flights we don’t need. That’s why I’m against a third runway at Heathrow and why I’m saying let’s really push forward with alternative ways of ensuring you can use non-flights for internal travel.”

He believes it will not happen in the next five years but nor will it take decades to realise.

“If you really push forward on High Speed 2 and really plan it in a proper way, you can move quickly…

“What I’m thinking is that if we can do a lot on public transport, we can bring some of that forward. Removing the stock of greenhouse gases that was put for 2045/50, you could bring that forward a lot earlier. Given the climate emergency, if you are not saying that, you are not being serious about it; to be brutal.

“When we publish our climate change policy paper for the autumn conference, you will see some proposals that are deemed at those people who fly the most pay the most. We are conscious some people fly once or twice a year for a family holiday; we’re not going to penalise them. But as we do this transition we want to ensure that people who fly a lot have to think carefully about those flights…We need a radical rethink of transport, which would be very popular.”

But with just days to go now before Monday’s announcement, Sir Ed is thinking about his own popularity.

It has been suggested that internal polling has placed him slightly ahead and that he has generally won the hustings with his rival.

“I’ve had a ball. I love campaigning. It’s like a holiday to me,” he declares.

“I am putting myself about and it’s having an impact…I have had a lot of people coming to the hustings, saying they are going to vote for Jo but come out saying they’re going to vote for me. So this is an extremely interesting competition.”

But can he defy the expectations of many at Westminster that his Scottish colleague will snatch the Lib Dem crown and succeed Sir Vince Cable? He adds quietly: “I sense it’s going to be very, very close.”