THERESA MAY lacks the authority to deliver a transitional Brexit deal and prevent an “economic cliff edge,” Labour’s Keir Starmer warned yesterday.

In a letter to the Prime Minister, the shadow Brexit secretary said the government’s EU withdrawal Bill was incompatible with her policy, which would axe the role of the European Court of Justice in March 2019.

He cautioned that she lacked the authority within her party to amend the Bill as 14 Conservative MPs, including senior Cabinet ministers, have given contradictory statements about her policy.