Tory remainers and Brexiteers rounded on Theresa May’s "shameful" leadership as rivals openly plotted to succeed her following her controversial request to extend Article 50 by three months.

The Prime Minister came under fire from all corners of her party as members of the influential European Research Group of Eurosceptic Tory MPs sent a letter to Downing Street setting out four demands for at this week’s EU Council meeting in order to get her Withdrawal Agreement through parliament.

The letter, signed by 39 MPs and seen by The Telegraph, tells Mrs May she should have "no reason to fear leaving on the 29th March".

Warning her not to delay Brexit if she values "our grassroots", the two-page letter calls on Mrs May to seek “legally binding changes to the Withdrawal Act, e.g. a unilateral exit clause, a legal end date or Malthouse Alternative Arrangements”.

It adds: “Please do not seek a long extension, this is neither needed nor desirable.”