PRESSURE was on Ed Miliband last night to rule out forming a new alliance with the Tories after an English Labour MP backed a “grand coalition” between the two parties.

Gisela Stuart said Labour should consider a deal with the Conservatives after May’s General Election that would see the two main Westminster parties united in government for the first time since they came together during the Second World War.

“If on May 8 you had a position where Labour had more seats than the Tories but not enough to form a government — but the Tories had more votes than Labour — I think you should not dismiss the possibility of a grand coalition in terms of regrouping of the main,” she told a London-based newspaper.

A series of polls in recent months have shown that Labour has haemorrhaged support in Scotland, which many commentators believe is due to the close alliance they formed with the Tories when the two parties, along with the Liberal Democrats, campaigned together for a No vote in September’s independence referendum.

Stuart, the Labour MP for Birmingham Edgbaston, is the latest Labour figure to promote a closer relationship between the two parties – historically regarded as ideologically incompatible.

Last month Labour peer Lord Moonie said a coalition with the Tories “would be better than one with the SNP”, while Robert James McNeill, a member of Labour’s Scottish policy forum and vice-chairman of East Lothian constituency Labour Party, suggested on Twitter that Labour voters in 16 Scots constituencies should vote for the Tories or Liberal Democrats in a bid to stop votes going to the SNP.

Stuart’s comments will be unpopular among the Labour party hierarchy north of the Border, which has been campaigning on the anti-nationalist platform that voting SNP will help return the Tories to power.

While Labour rubbished Stuart’s comments – describing them as “utter nonsense” – they are not as far-fetched as party bosses suggest. Vince Cable, the LibDem Business Secretary, made comments similar to Stuart’s in January, saying: “We may have to prepare ourselves for the possibility that we won’t be in the coalition at all, that there will be a grand coalition between Labour and the Tories instead.”

And Ian Birrell, a former speech writer to David Cameron, said: “Regardless of the personalities and positions, the two parties could start to hammer out those huge issues confronting the nation that conventional politics seems incapable of solving.”

A coalition between the main parties of the left and the right is in place in Germany, Stuart’s country of birth, where Angela Merkel’s CDU is in government with the Social Democrats.

Angus Robertson, the SNP MP, said Stuart’s comments reflected the close working relationship that was forged between Labour and the Tories during the independence referendum campaign and which has continued at Westminster.

“Labour has already spent two-and-a-half years working hand-in-glove with the Tories in the referendum campaign, and that has continued in votes at Westminster to impose £30 billion more austerity cuts – so it’s no great surprise to see yet another senior figure in the party call for this toxic alliance to continue,” he said.

“With Labour members, Lords and now even MPs backing working with the Tories, it is no wonder that far more people trust the SNP rather than Labour to keep the Tories out of government.”

He added: “Communities across Scotland are already hurting thanks to the austerity agenda of this right-wing government – and another five years of the Tory cuts would have a devastating impact. This is exactly why the SNP has been clear that under no circumstances would we prop up a Tory government – unlike senior Labour figures.”

A bombshell poll for former Tory donor Lord Ashcroft last month predicted a Labour wipe-out in Scotland as voters turned their backs on the party once perceived as the Tories’ strongest critics.

It suggested that Douglas Alexander, Labour’s campaign chief and Shadow Foreign Secretary, would lose his seat, while Margaret Curran, the Shadow Scottish secretary, and Anas Sarwar, former deputy leader, would also go.

The poll of more than 16,000 voters in Scotland predicted the SNP would take 15 of 16 crucial marginal seats in the country with an overall 25.4 per cent swing.

If replicated on May 7, Labour would lose 35 of its 41 MPs and all but rob Labour leader Ed Miliband of any chance of winning an overall majority.

The Ashcroft poll followed a previous survey by Survation in December which also brought bad news for Labour in Scotland.

The poll, the first to be released since Jim Murphy took over as leader in Scotland , found 48 per cent of Scottish voters were planning to support the SNP in May, compared to 24 per cent for Labour.

Labour and the Tories were united in a grand coalition at Westminster in the Second World War after Winston Churchill, in his first act as prime minister in 1940, invited the leaders of the Labour, Liberal and Conservative parties – Attlee, Sinclair and Chamberlain – to join the government. This administration mobilised Britain for total war.

Responding to Stuart’s comments on a new grand coalition between Labour and the Tories, a Scottish Labour spokesman said: “This will never happen.”