AN independent Scotland would be England's "best pal in the world", First Minister Alex Salmond has said.

The SNP leader also promised a series of "amazements" between now and September's referendum to convince Scots to vote Yes.

His comments came as a poll suggested support for independence is growing. The ICM survey found 37% of those asked said they would vote Yes, up from 32% in a similar poll last September.

Around 44% said they would vote No, down from 49% in September, while the number who said they had yet to make up their mind was 19%.

Pro-independence campaigners hailed the swing towards a Yes vote as "very significant".

Deputy First Minister Nicola Sturgeon said it was a sign voters have taken the time to digest the Scottish Government's flagship White Paper on independence, published in November.

But Alistair Darling, the leader of the pro-Union Better Together campaign, cautioned against reading too much into one poll.

"You have to look at all the ­opinion polls you have, not just one particular one," he said."What I would say though, and I've been saying this for some time, I do think that this referendum is going to be far closer than people think."

Better Together also released a dossier detailing the concerns of 50 economic and academic experts over Scottish ministers' plans for a currency union with England.

They include John Nugee, a former Bank of England chief manager, who warned such a union is not in Alex Salmond's power - and English voters could block it.

In a separate development, Scottish Secretary Alistair Carmichael has called for a "product recall" for the White Paper, describing it as having developed so many faults it is "more of a black mark than a blueprint".

Asked about plans to increase support for independence in the run-up to the vote, Mr Salmond told the Sky News Murnaghan programme: "I have absolutely no doubt there'll be a range of amazements over the next eight months or so."

After independence, Scotland would be England's "best pal in the world", he said, adding that the move would be good news for England and other parts of the UK. He said councils in the north of England saw an opportunity in Scottish independence.

"They want closer relationships with Scotland … and the reason for that, of course, is they see the power centre moving north as a potential benefit," he said.

Mr Salmond will travel to London this week to meet ­ambassadors from European Union member states thought to include Poland. He is also expected to meet ­Governor of the Bank of England Mark Carney soon, possibly when the Canadian visits Scotland this week.

Despite Mr Salmond's ­"amazements" comment, Stephen Noon, chief strategist of the Yes campaign, has warned against expecting "one big event" to define the independence debate.

"It's good for a headline and adds to the potential excitement in what is already a long campaign," he said over the weekend, adding: "I will be content with victory delivered on a slow burn."

The ICM poll surveyed more than 1000 people over 16 between January 21 and 24.

A YouGov poll for Sky News asked 840 Scots how they would feel if they woke up to find Scotland was independent.

It found 46% would be dismayed, 25% delighted, 17% wouldn't mind and 11% did not know.

Of 1695 people in England and Wales asked the question, almost half wouldn't mind, 34% were dismayed and 11% were delighted.

At the weekend pollsters suggested class could help decide how Scots cast their vote. Ipsos MORI said that affluence or a lack of it gave the clearest indication of how people might vote.

It has also emerged that expat Scots in other parts of the UK could sue over their lack of a referendum vote. A trainee lawyer from Dumfries based in London, James Wallace, claims the vote is unconstitutional.

His potential challenge has reportedly won the support of other expatriates such as Kenny Logan, the former Scottish rugby union player.

Referendum voting entitlement is based on residency in line with rules for the 2011 Holyrood poll..