SCOTLAND faces the prospect of leaving the European Union despite a majority of Scots wanting to remain part of the 28 state bloc, according to a new poll.

The Survation poll found 51 per cent of people across the UK would vote to leave if the referendum were held tomorrow, compared with 49 per cent who wanted to stay.

But in Scotland the result was reversed, with 49 per cent saying they would vote to leave the EU and 51 per cent wanting to stay.

The results do not count those who were undecided or said they were unlikely to vote.

Survation questioned 1004 people across the UK between September 3 and 4.

The comparison between Scotland and the rest of the UK is based on the very small sample of Scots, fewer than 100, who took part.

However, it will re-focus attention on the possibility of a second independence referendum within the next five years.

Despite describing last year's vote as a "once in a generation" event, First Minister Nicola Sturgeon has said a second referendum could be held sooner if there is a "material change" in Scotland's circumstances.

The main example she has given is the possibility of Scotland leaving the EU against the wishes of most Scots.

Her position is expected to form the basis of a heavily qualified promise of a second independence referendum in the SNP's election manifesto next year.

There would also have to be strong public support for a second independence vote, as Ms Sturgeon has said repeatedly it would be for "people to decide" the timing.

Survation found significant national and regional differences over the question of Britain's continued membership of the EU among those had had made up their minds and were likely to vote.

Wales was the most pro-EU part of the UK, with 56 per cent wanting to stay and 44 per cent saying they would vote to leave.

Londoners were also in favour of staying, by 52 per cent to 48 per cent, a slightly bigger margin than in Scotland.

However, a majority of people in the North of England, the South and the Midlands said they would vote to quit the EU.

The poll found around one in five voters were undecided.

The neck-and-neck findings suggest they will decide whether Britain stays in the EU when the referendum is held at some point before the end of 2017.

The findings run counter to other recent surveys which have consistently shown a comfortable majorities for staying in the EU.

As recently as July, a Survation poll gave the "In" camp a 54 per cent to 46 per cent advantage.

However, the findings echo previous polls which have shown slightly higher levels of support for the EU in Scotland than across the UK as a whole.

The latest survey, for a Sunday newspaper, came as MPs prepared to debate the EU referendum on their return to the Commons this week.

Prime Minister David Cameron is facing fresh opposition over the ground rules of the campaign.

Last week he bowed to pressure and agreed the government should abide by a "purdah" period preventing minister from making announcements likely to influence the result during the latter stages of the campaign.

The strongly pro-EU SNP has called on him to go further, however, by imposing sanctions on ministers and civil servants who break the rule.

SNP foreign affairs spokesman Alex Salmond claimed ministers breached purdah rules during the independence campaign.

He added: "Political debate is good for democracy but only if it is done to the highest of standards, David Cameron’s current half-hearted approach needs to be corrected and the SNP will lead that charge in the Commons."

The strongly-pro SNP is expected to be a major voice in the campaign to keep Britain in the EU.