The Attorney General has abandoned attempts to secure a hard time-limit or unilateral exit mechanism from the Irish backstop, The Telegraph has been told.

Ministers briefed on Geoffrey Cox's approach said those aims, which represent the central demands of Eurosceptics, are considered too "blunt" and have been rejected by the European Union.

Some Cabinet ministers are already resigned to the Prime Minister losing a second meaningful vote on her deal amid concerns that changes to the backstop secured by Mr Cox will not be sufficient to win round Brexiteers.

The Attorney General is understood to be focusing on securing an enhanced "arbitration mechanism" that allows the UK or the EU to provide formal notice that the backstop should come to an end.

The EU is, however, resisting demands by British negotiators for an "independent" arbitration panel, outside the jurisdiction of the European Court of Justice.