THE SNP’s Stewart McDonald has raised the prospect of a post-election pact between his party and Labour with the price of the Nationalists’ involvement being a Jeremy Corbyn pledge to scrap Trident.

Speaking to Westminster’s House magazine ahead of this weekend’s SNP conference, the party’s defence spokesman suggested that the possibility of a snap General Election - with the possibility of another hung Parliament - would hand the country’s anti-nuclear movement an “historic” opportunity, one that the Labour leader and lifelong unilateralist would be “mad” not to take.

He said: "On the issue of nuclear weapons, of course, there has to be a serious discussion that says: ‘You want to get rid of them, we want to get rid of them, let’s work out a way we can make that happen.’

“I hope that if Jeremy’s in the position to form a government - perhaps with an arrangement with the Scottish National Party - then that [scrapping Trident] should be one of the key planks of any discussion that we have. Because Corbyn agrees with us on this. He has a long and honourable history of agreeing with us on this.”

The Glasgow South MP - noting how a desire to rid Scotland of nuclear weapons was a “driving thread” through the history of the SNP and the wider independence movement - went on: “We’d ultimately have an opportunity, the first opportunity that would have presented itself in British history, for Britain to get rid of nuclear weapons. We would be mad, and Jeremy Corbyn would be mad, not to grab that opportunity.”

Asked if scrapping Trident should be a red line for Nicola Sturgeon in forming any post-election pact, Mr McDonald stressed: “The red lines will be decided by the First Minister and it’s entirely sensible that she is able to set those red lines.

“But knowing the First Minister as I do, as a lifelong anti-nuclear campaigner - in fact, I think she joined the CND before she joined the SNP - that’s going to be pretty high up on her agenda; of course, it is.”

In the interview, Mr McDonald makes clear opposition to Trident centres not just on a philosophical point but also on the huge cost of the programme at a time when the country is facing a series of security threats. “The threats now are from terrorist organisations, cyber, the type of attack we saw in Salisbury. We’re not going to use nuclear weapons against any of those,” he argued.

With the issue of a second independence referendum set to dominate the SNP conference, the Nationalist backbencher said he trusted Nicola Sturgeon to “make the right call” on timing.

He went on: “I’m not really fussed when she announces it. I care about getting it right rather than getting it quickly.

“My own sense is that we need to be a bit clearer on what Brexit’s going to look like. If the public have got any sense that this has been rushed or even hijacked, they won’t thank us for it,” added Mr McDonald.