Jean-Claude Juncker fears Theresa May’s Government could collapse next week if Brexit talks remain deadlocked, The Telegraph has learnt.

The European Commission president will extend the deadline for Mrs May to settle a dispute over the Irish border to the eve of an EU leaders’ summit next Thursday to maximise her chances of success.

It comes as Mrs May’s own MPs warned her she could be toppled “within weeks” if she comes back from Brussels next week without an agreement that trade talks can begin.

Meanwhile, Leo Varadkar, the Irish prime minister, revealed on Wednesday night that Mrs May hoped to offer a new version of the Irish border agreement either later that night or on Thursday.

The Irish border agreement - which would have meant the UK agreeing to "regulatory alignment" between Northern Ireland and the Republic to avoid a hard border - fell apart on Monday after the proposals were rejected by the Democratic Unionist Party (DUP.)

However, Mr Varadkar revealed during a joint press conference in Dublin with Dutch Prime Minister Mark Rutte on Wednesday night that talks were now back on track following a phone call with the prime minister.