Nicola Sturgeon has warned that the Scottish Parliament could try and block the UK leaving the EU using an obscure legal mechanism even if it infuriates the English.

The First Minister said she believes Westminster requires a legislative consent motion (LCM) from the Scottish Parliament to enact Brexit as it impacts directly on the latter’s devolved responsibilities.

She confirmed that SNP MSPs would seek to block any such motion, even if this prevented the UK from leaving the EU, in order to reflect the overwhelming Remain vote in Scotland. The SDLP later echoed her intervention, warning the Northern Irish “have the right to say no”.

The threat raises the prospect of a prolonged legal battle over enacting the result of last Thursday’s referendum, which saw the Scots and Northern Irish vote by overwhelming margins to Remain.

But David Mundell, the Scottish Secretary, and Theresa Villiers, his Northern Irish counterpart, said the devolved administrations cannot veto Brexit. James Chalmers, Regius Professor of Law at the University of Glasgow, said they could only make the process more “awkward” by rejecting the LCM.

In a series of TV interviews on Sunday morning, Ms Sturgeon also warned that the next Prime Minister would be fighting a losing battle to stop her staging a second independence referendum and argued that the UK that Scots voted to remain in two years ago no longer exists.