A HIGH number of undecided voters in Scotland will decide the outcome of the general election UK-wide and may yet prompt a Labour revival north of the border, Jim Murphy has claimed.

A TNS poll, published this week, gave the SNP a huge lead over Labour, putting the party on course to win 56 of Scotland's 59 seats. The nationalists have support of 52 per cent nationwide, the survey found, compared to 24 per cent for Labour.

However, it also revealed that there are large numbers of undecided voters. Across Scotland, almost a third are yet to make up their minds, while in the key battleground of Glasgow, the total rises to 39 per cent.

While Tom Costley, head of TNS Scotland, said there was evidence that the increasing SNP lead was down to disaffected Labour voters swinging behind the nationalists, he added that the campaign was "only beginning".

Mr Murphy insisted that remained confident that he would "turn these polls around" yesterday, with targeting undecided voters set to form a key part of his strategy in the final weeks of campaigning.

The Scottish Labour leader said: "There's a long, long way to go. In a lot of constituencies more than a third of all the voters are undecided. I know most of those people are people who have traditionally voted Labour. We're making a vast effort, and talking to them each individually, because they'll decide the outcome of the election here in Scotland.

"With the polls being so tight across the rest of the UK, that third of Scottish voters who are undecided will decide the fate of the entire UK election. They'll decide whether there's a Labour Government or a Tory Government, we all know there's not going to be a coalition between Labour and the SNP, under any circumstances."

Angus Robertson, the SNP's campaign director, said that Labour were continuing to pay a heavy price for a "toxic alliance" with the Tories during the referendum campaign.

He added: "Polls show that more and more people across Scotland are putting their faith in the SNP to stand up for Scotland's interests at Westminster. But we are taking absolutely nothing for granted and are fighting hard for every seat and every vote."