The SNP's Holyrood pact with the Scottish Greens will remain in place until 2026, according to the party's former leader at Westminster.

Appearing at the Edinburgh Fringe Festival this afternoon Ian Blackford defended the Bute House Agreement behind the SNP-Green joint government deal.

A series of figures in the SNP have raised concerns about the arrangement with some calling for party members to have a vote on whether the pact should continue.

In an article in the Herald on Sunday today former rural affairs secretary Fergus Ewing said the Greens "basically would destroy our economy" and the deal could down the SNP and the independence cause. He repeated his previous calls for the pact to end.

But Mr Blackford disagreed.

He told a festival audience: "The Bute House Agreement was the right thing to do, it remains the right thing to do, and it will remain in place over the lifetime of this parliament."

The MP was speaking at For The Many Live with broadcaster Iain Dale and former Labour Home Secretary Jacqui Smith at Pleasance EICC.

Asked about Alba's idea of Yes parties fighting elections on a single 'Scotland United' ticket, Mr Blackford dismissed it as "for the birds".

He said: "Let's just remember that we've had the council elections not that long ago in Scotland, 1100 seats up for grabs. The Alba party won zero.

"So the idea that there is scope for an electoral alliance where our cause will be assisted by making an alignment with other parties I'm afraid is for the birds."

Asked if he would like to see Alex Salmond back in the SNP, Mr Blackford was blunt.

He said: "Alex Salmond is not in the SNP. He's in another party. There is no pathway for Alex Salmond to return."