A PROMINENT SNP MP yesterday joined the newly-formed Alba party – as Nicola Sturgeon said there are “significant questions” about Alex Salmond’s return to politics.

Former justice secretary Kenny MacAskill will stand to be an MSP on the Lothian regional list and is now the Alba Party’s first MP at Westminster, it was announced yesterday.

He is the first big SNP name to defect to the new party, although former SNP councillor Chris McEleny is also standing as a candidate.

But the SNP called for him to resign his House of Commons seat, saying his departure from the party was “somewhat of a relief”.

Former Ayr MP Corri Wilson has also defected to the new party, which was launched on Friday with the aim of creating a “supermajority” of pro-independence supporters in Holyrood.

Salmond also confirmed he will be standing on the North East regional list in May’s Scottish Parliament election.

READ MORE: Another SNP MP defects to Alex Salmond's Alba Party for Holyrood election

Speaking on the campaign trail yesterday, Sturgeon said: “I take no pleasure whatsoever in saying this but I think there are significant questions about the appropriateness of his return to public office given the concerns that have been raised about his behaviour previously but that’s for voters to judge and decide.

“This is an election. We live in a democracy. For my part, in this campaign, I am focused on the interests of the country.”

Asked about Salmond’s vision of securing a “supermajority”, she added: “I know Alex Salmond very well. He makes big claims which often don’t stand up to scrutiny.”

She said her predecessor has changed his mind on how to secure independence due to “self-interest and, dare I say it, ego”.

She added: “Alex Salmond is a gambler. It is what he enjoys doing. But this is not the time to gamble with the future of the country.”

READ MORE: Nicola Sturgeon responds to Alba Party: 'Elections are not games'

MacAskill, the MP for East Lothian, wrote to his staff saying: “I will be joining the newly-formed Alba Party to deliver than supermajority for independence through the list vote and which I believe’s essential to achieving our nation’s independence.”

In a column published yesterday he said there had been some internal dissent within the SNP and a “new political home will appeal to many”.

And speaking in a television interview later he said: “I’m going to continue to argue for the cause of independence to make sure we deliver that independence supermajority which can actually allow Scotland to be all the things we know it can be.

“The time for just sitting supinely taking abuse from Mr Johnson in Westminster is long past, the risk to Scotland is too great.”

However in response to his defection, Westminster SNP leader Ian Blackford said: “After yesterday’s events this is the second least surprising news in Scottish politics.

“He has been an increasing embarrassment to many in the SNP and his departure is somewhat of a relief.

“That he is joining a party with serious questions to answer about its leader’s suitability for public office is no surprise.

“He should now resign his seat in the House of Commons to let a by-election take place immediately so the people of East Lothian can elect a new MP who will focus on their interests, rather than self-interest.”

The Alba Party will only be standing candidates in the regional lists in an attempt to boost pro-independence numbers in Holyrood.

Launching the party in an online event on Friday, Salmond said: “Today Alba are hoisting a flag in the wind, planting our Saltire on a hill. In the next few weeks we will see how many will rally to our standard.”

He has claimed that Alba winning regional list seats could lead to 90 or more MSPs at Holyrood who support independence.

Yesterday Damian Lyons Lowe, chief executive of Survation, said if five percentage points of the SNP’s current support on the regional lists went to Alba and it also took two points from the Scottish Greens, then the projected pro-independence ­majority would increase from 78 to 83.

Polling expert Mark Diffley described it as a “very risky” strategy for Salmond. He said: “What he is essentially arguing is that voters should be gaming the system.

“It is true to say ... the SNP tends to do much better on the constituency vote than it does on the regional vote in terms of the number of MSPs that it achieves and therefore a [regional] vote for the SNP is what he would see as a ‘wasted’ vote.

“That is the theory but it does rely on a few things and it may or may not come true.”

Diffley said it was difficult to predict the impact without any polling data on Alba, but added: “You could argue that given how the system works, you could end up with more pro-Union MSPs than pro-independence MSPs as a result.”