THE summit to a Brexit deal is “still shrouded in mist” Boris Johnson has told Tory MPs but he insists there is still a chance of getting to the mountain top to secure a new withdrawal agreement at this week’s two-day European Council.

The Prime Minister addressed Conservative colleagues in the House of Commons after he chaired a meeting of the Cabinet, making clear there remained what a Downing St source described as “thorny issues”.

These primarily involve Northern Ireland and the subjects of consent and customs.

Steve Baker, the ardent Tory Brexiteer who chairs the Eurosceptic ERG faction, said following a meeting of the Conservatives' 1922 backbench committee that he had been reassured on both matters concerning Northern Ireland.

“The DUP’s redline is that the whole of the UK needs to leave the customs union and be in its own single customs territory and the PM has just told us that is what he is going to do.

“The DUP’s other most important redline is consent in relation to regulatory alignment and that I understand will also be carried through; the PM made it clear.”

The former Brexit minister went on: “It’s not our job to be more Unionist than the DUP but equally we are not delegating a decision to anybody else either; each one of us must make our decision.

“But it should be obvious to anyone by now that we very much hope the PM succeeds in presenting us with a Withdrawal Agreement and Political Declaration on the future relationship. That’s what we are hoping for.”

Asked about people’s fears of a sell-out on the Union if there is a border down the Irish Sea, Mr Baker replied: “No. I would not accept any allegation of a sell-out on the Union.”

Asked if Mr Johnson sounded confident of getting a deal in the next 24 hours, the Buckinghamshire MP replied: “A deal is to be done but we are not yet there. He was talking about being on the Hillary Step on our way up to Everest but the summit is still shrouded in mist.”

However, following the backbench meeting Alister Jack, the Scottish Secretary, told The Herald that he was "optimistic" a deal would be struck. Asked why, he replied: "Because we are very close."

After the positive language on both sides of the Channel earlier this week officials were adopting a more subdued tone, accepting that as the start of the European Council tomorrow afternoon approaches numerous obstacles still needed to be surmounted for a fresh agreement to be brokered.

On Wednesday evening, Michel Barnier, the EU's chief negotiator, was set to brief EU ambassadors on the state of play.

The PM needs to get a deal approved at the Brussels summit on Thursday if he is to avoid an almighty clash over asking for a delay to the UK's departure.

His spokesman explained how Mr Johnson had updated his Cabinet, which gave its "full support" to get a deal ahead of the summit following a "positive discussion".

"He said there was a chance of securing a good deal but we are not there yet and there remain outstanding issues," said the spokesman.

Earlier in the day, Stephen Barclay, the Brexit Secretary, confirmed the PM, as set out by the Government in papers released at the Scottish courts, would write a letter asking for an Article 50 extension if no-deal was in place by Saturday; something the PM has repeatedly ruled out.

Talks in Brussels resumed on Wednesday morning after running into the early hours.

After a briefing by Mr Barnier, Dmitris Avramopoulos, the EU Commissioner, said: "Talks have been constructive but there still remains a number of significant issues to resolve."

Donald Tusk, the European Council President, told Poland's TVN 24 news channel that "everything should be clear" by midnight; an assertion that raised eyebrows in No 10.

Arlene Foster, the DUP leader, quickly moved to reject a suggestion that her party had accepted the latest proposal on consent.

She tweeted: "Discussions continue. Needs to be a sensible deal which Unionists and Nationalists can support."

Leo Varadkar, the Irish premier, said he was "confident" a deal could be struck by the current deadline and raised the prospect of another EU summit being held in the coming weeks.

But he warned there were still numerous hurdles in the way, after speaking with Mr Johnson and the European Commission on Wednesday morning.

"There is a pathway to a possible deal but there are many issues that still need to be resolved, particularly around the consent mechanism and issues around customs and VAT," he said.

"Although time is running short, I am confident these objectives can be achieved," added the Taoiseach.

And Saturday is a key date for the Prime Minister, with the Benn Act passed by MPs trying to prevent a no-deal Brexit stating he must write to Brussels asking for a delay if Parliament does not agree to a deal by then.

Mr Barclay was questioned by the legislation's namesake, Labour's Hilary Benn, when appearing at the Exiting the European Union Committee of MPs.

The Brexit Secretary reiterated that the PM would write to Brussels asking for an Article 50 extension, as previously revealed in documents submitted during a Scottish court challenge.

"I can confirm, as the Prime Minister has repeatedly set out, that firstly the Government will comply with the law, and secondly it will comply with undertakings given to the court in respect of the law," he said.

Mr Barclay confirmed that the Government "will abide by" what is set out in that letter, following fears the Prime Minister could try to scupper an extension with a second contradictory letter or request to a member state to block an extension.

The Cabinet minister reiterated the Government's commitment to leave the EU on the current October 31 deadline, despite the act demanding a delay to the end of January if MPs do not approve a deal by Saturday.

If Mr Johnson succeeded in bringing a deal home to the UK, he would then face a battle to do what Theresa May failed to do three times and get it approved by Parliament.

Labour leader Jeremy Corbyn said he was "deeply concerned" about the negotiations and ruled out his party backing a deal under Mr Johnson's reported terms.

The DUP's MPs and their influence over the Tories are key in swinging any vote Mr Johnson's way, and he was to meet them for the third time in as many days on Wednesday afternoon.

Talks between Mr Johnson’s team and the Tory ERG Brexiteers, the so-called “Spartans” were also expected to continue.

But a split among the hardliners became visible over earlier reports that Mr Johnson might agree to a customs border down the Irish Sea, a move Owen Paterson, the former Northern Ireland Secretary, made clear would be "unacceptable".

Yet Jacob Rees-Mogg, the Commons leader and a former ERG chair, said he believed an agreement could be accepted by MPs, telling LBC radio: "The votes are there now for a deal."

The DUP has helped prop up the Tory administration following increased funding from Mr Johnson's predecessor in Number 10 as part of a confidence and supply deal, in a £1 billion package branded a "bribe".

There is speculation that more money could be headed in the direction of Ms Foster's party as the PM tries to get them on board with any concessions.

The DUP were decidedly lukewarm on the mooted proposals in a statement after their second audience with Mr Johnson in as many days, with a spokesman saying "gaps remain and further work is required".

David Davis, the former Brexit Secretary, said DUP backing would be influential for his colleagues.

"There will be quite a lot of Tory MPs who will take their line from what the DUP do," he told BBC Radio 4's Today programme.

Pressure to sign off on a draft agreement is peaking. A legal text needs to be published ahead of the summit if the EU27 are to consider ratifying the Withdrawal Agreement at the two-day summit.

Their approval would allow Mr Johnson to put the deal to MPs in a proposed extraordinary sitting of Parliament on Saturday, between 9.30am and 2pm.

The Government is set to table a motion on Wednesday evening to ask Parliament to back the sitting, the first on a Saturday for 37 years.

During the weekend session, MPs would be able to back or reject any deal presented to them, or discuss what to do next in the Brexit saga.