The debate on independence will stop if the SNP lose the general election in Scotland, one of the party’s MPs has said.

The party has said it will put the issue at the heart of its manifesto, agreeing at its conference that a majority of MPs north of the border after the next vote will be a mandate to give “democratic effect” to Scottish independence.

But writing in the Sunday National, senior MP Tommy Sheppard urged Scots not to abandon the party in favour of Labour to ensure the Tories lose.

Sir Keir Starmer’s party, he wrote, has already won the vote and will take Downing Street following the election, but the SNP losing its Westminster majority in Scotland would dash the hopes of independence.

“We need to be very clear with the electorate, this year’s vote is about whether the journey continues, whether we can create circumstances to move towards our independence,” he wrote.

“And with a corrupt first-past-the-post system, the only way to do that is to vote SNP.”

Mr Sheppard added: “If the SNP lose the election in Scotland, the debate on independence stops.

“That is why we must put aside our differences and unite.”

His call for unity could be seen as an attempt to ward off any traditional independence supporters from supporting other such parties, most notably the Alex Salmond-led Alba Party.

The MP, who was first elected in the SNP surge of 2015, said a win for the party would allow them to “press that mandate” against an incoming UK government, adding that anyone “who believes Scotland should become independent, or even that we should have the choice to do so, ought to vote SNP”.

According to Scottish Tory constitution spokesman Donald Cameron, the debate on independence should have stopped after the 2014 referendum.

“Tommy Sheppard is just trying desperately to find some excuse for people to back the SNP, a party which has been a disaster in government and, as usual, is focusing on separatism, rather than people’s real priorities,” he said.

“The Scottish Conservatives have provided the only robust opposition to the SNP’s divisive agenda and, in many seats, are the only way to get them out of office.”