Former Scottish Government minister Alex Neil has revealed that he secretly voted to leave the European Union in the June referendum.

Mr Neil told The Daily Telegraph that he decided to vote for Brexit 10 days before the referendum but did not make his choice public as he did not want to ‘rock the boat’.

He said that an increase in support for right-wing parties in Europe and the austerity measures imposed on Greece and Portugal by the EU had influenced his decision. However, it was George Osborne’s threat of an emergency Brexit budget that persuaded him.

The MSP for Airdrie & Shotts, who served in Nicola Sturgeon and Alex Salmond’s administrations, also claimed that several other SNP MSPs had told him that they had voted to leave the EU.

Read more: Former minister Alex Neil to join Brexit 'awkward squad' as SNP divisions spill into open

He said: “There’s a number of my colleagues who have spoken to me privately who did the same. They don’t want to broadcast it. They were betwixt and between and they voted to leave.”

Mr Neil said that Scotland could face a similar fate to Greece and Portugal if it remains in the EU because of its deficit.

The former health minister also claimed that tying a second Scottish independence referendum to the EU could reduce the SNP’s chances of winning, warning that Brexit backing Scots may not want to leave the UK for Europe.

The Herald revealed yesterday that Mr Neil is part of a formal Cross Party Group on Brexit which will acknowledge potential upsides, along with challenges, of leaving the EU.

He has previously argued that the SNP should use Brexit to achieve new powers for Holyrood and ‘neo-independence’.

Read more: Former minister Alex Neil to join Brexit 'awkward squad' as SNP divisions spill into open

His admission came as the High Court ruled the UK Government would not be able to start Brexit without giving MPs a vote on triggering Article 50.

Scottish Conservative constitution spokesman Adam Tomkins has now called on the SNP MSPs who backed Brexit to "show some gumption" and come forward.

He said: "How can Nicola Sturgeon use this vote to whip up grievance and claim independence must now be 'on the table' when several of her own MSPs backed it?

"In the Scottish Conservatives, we had Leavers and Remainers and MSPs were allowed to campaign on both sides.

"The SNP's 'silent Brexiteers' now need to come forward openly and let their constituents know how they voted."

Scottish Liberal Democrat leader Willie Rennie said: "Today's revelation is of no real surprise considering the First Minister herself kept telling her supporters that we'd have another independence referendum if the UK voted to leave the EU.

"Instead of gambling with the livelihood of those who will be negatively impacted by Brexit, the First Minister can redeem herself if she joins the Liberal Democrats in helping keep the UK within the EU."

Scottish Secretary David Mundell said the "evidence suggests that about 500,000 SNP supporters voted to leave the EU" in June's referendum.

The Tory said the First Minister had "failed to recognise that a million people in Scotland voted to leave, including about 500,000 of her own supporters".

He added: "What those people want, as well as as most remain voters, is for her to get on with negotiating a deal with Scotland and the UK, and not constantly trying to pick fights and not trying to create chaos and uncertainty so she can take forward another independence referendum.

"The First Minister doesn't speak for all remain voters in Scotland, most people like me who voted to remain didn't do so on the basis that if we didn't get our way we'd be torn out of the United Kingdom, which seems to be her logic."

Labour's Europe spokesman Lewis Macdonald said: "It's no real surprise that Alex Neil and other SNP MSPs voted to leave, since many of the million Leave voters in Scotland were also SNP supporters.

"It strikes many Scots as odd for the SNP to be in favour of one political union but not the other, so at least Alex Neil is consistent.

"The reality is Scotland is now faced with two nationalist governments, both promoting their own brand of political separation.

"Only Labour stands for what the majority of Scots want - a strong Scottish Parliament which is part of the UK with a close relationship with Europe."