Labour is failing to catch the SNP in Scotland and support for the nationalists is still on the rise, a new poll has suggested.

With Scotland set to play a crucial role in determining the outcome of the General Election, the study suggests Ed Miliband's party could suffer huge losses north of the border on May 7.

Just over a quarter (27%) of Scots say they will be voting for Labour in the election, according to the Panelbase poll for the Sunday Times, a drop of two points from earlier this month.

In contrast, support for the SNP is up by three points to stand at 48%, the research found.

Meanwhile, 16% said they will be voting Conservative, 4% back the Liberal Democrats, 3% support Ukip and 2% will vote Green.

Labour won 41 seats in Scotland in the 2010 election but that could be slashed to just five after May 7, the research suggests.

At the same time, the SNP could see the number of MPs it has rise from six to 53. The Liberal Democrats could lose all but one of the 11 seats they won five years ago, while Scotland could have no Conservative MPs.

Panelbase questioned 1,044 voters in Scotland between April 20 and April 23, with SNP election campaign director Angus Robertson saying the results are a "further indication that the momentum in this campaign is firmly with the SNP".

Mr Robertson said support for the SNP has "risen even further in the last three weeks" while backing for the Labour Party, which is led in Scotland by Jim Murphy, has fallen.

"Of course we are taking absolutely nothing for granted and will continue to work as hard as we can to win the trust of people across Scotland," Mr Robertson said.

"The SNP are committed to working with other progressive voices from across the UK to achieve an alternative to cuts - and this poll is the latest indication that people are backing the SNP to make Scotland stronger at Westminster."

Former Labour first minister Lord McConnell claimed a "protest movement" had caused the surge in support for the SNP, as he warned people a UK General Election was not the place to make that protest.

"The General Election is not a protest by-election," the former Scottish Labour leader told the Sunday Post newspaper.

"In the next 10 days we will choose the government of the country, not just someone to represent each of our local areas.

"I know the vast majority of people thinking about voting SNP want to see change in Scotland and in the UK, and they are impatient like me.

"But they need to make a better choice to bring about that change."