A war of words broke out last night after a Labour amendment to “protect Scottish devolution” was defeated in the House of Commons.

The 13 Scottish Tory MPs voted with the UK Government to defeat the Opposition’s move, which lost by 321 votes to 297, a majority of 24.

Lesley Laird, the Shadow Scottish Secretary, said: “The Scottish Tories rolled over to protect their party instead of protecting the devolution settlement. They gave excuses but could offer no substantial reasons why they would not support Labour’s amendment to Clause 11.”

Stephen Gethins, the SNP’s Europe spokesman, accused the Scottish Conservatives of a “shameful abdication of duty” in preventing what the Nationalists believe is a “power-grab”.

But Tory sources accused the opposition parties of “spouting hot air” and branded Labour’s amendment a “political stunt”.

During earlier Commons exchanges, Stephen Kerr, the Conservative MP for Stirling, expressed his “intense disappointment” that the Government was not, as promised, amending the bill in the Commons; it will do so in the Lords.

But he stressed: “There is no point creating an amendment which then itself has to be amended.”

The SNP’s Pete Wishart insisted it was incumbent on Theresa May to remove the “devolution threat” from the legislation but Mr Kerr accused the Perth MP of creating a “grotesque grievance” when none existed and said the Prime Minister was going to “extraordinary lengths” to achieve consensus and change the bill so that it was fit for purpose.