East Lothian MP, Kenny MacAskill, has announced he's joining the Alba Party.

The former justice secretary will now head the new party’s Lothian list.

In an open letter to his party workers, the East Lothian MP said: “I will be joining the newly formed Alba Party to deliver the supermajority for independence through the list vote and which I believe’s essential to achieving our nation’s independence.”

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MacAskill was Alex Salmond’s Justice Secretary at Holyrood.

SNP Westminster Leader Ian Blackford MP 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."

READ MORE: Alex Salmond: Alba stands as a party to boost pro-independence MSPs - but it may cost SNP majority

Former SNP MP Corrie Wilson has also joined the newly former Alba Party. 

Wilson added she plans to stand in the South of Scotland list saying: “I am delighted to be joining the Alba Party whose goal is to secure independence for Scotland – the cause that so many in Scotland have given so much to support.

“I believe we have a fantastic opportunity at this election to work with others to deliver an independence #supermajority leaving Boris and co in no doubt that we are ready for self-determination.”

Shadow Secretary of State for Scotland Ian Murray MP said: "The already thin veneer that separated Alex Salmond's party from the SNP has totally cracked in just 24 hours.

"The Scottish and Westminster Parliaments are not places for people to play at politics and Kenny McAskill must now stand down to allow the people of East Lothian to make his obsession with division history. The people of East Lothian deserve better than to be cast aside without a second thought.

"But what is now crystal clear for all of Scotland to see is that this new outfit just shares the same obsession with reheating old arguments as Nicola Sturgeon and the SNP.

"The truth is Scotland deserves better - and that is why Scottish Labour will focus on delivering a national recovery plan so we can build a fairer and stronger Scotland together."