Theresa May left Brussels on Monday without an securing an agreement on the terms of Britain's withdrawal from the European Union

Theresa May is trying to keep her Brexit plans afloat today after her Northern Irish political partners blocked her attempts to secure a withdrawal agreement with the EU.

The Prime Minister was set to call the leader of the Democratic Unionist Party to convince her to back her proposals for what should happen with Northern Ireland’s land border after Brexit.

Downing Street has indicated Ms May hoped to be back in Brussels before the end of the week to secure the agreement, after the DUP refused to accept plans that could have seen Belfast following a different regulatory regime than London.

Brexit: the deciders Show all 8 1 /8 Brexit: the deciders Brexit: the deciders European Union's chief Brexit negotiator, Michel Barnier Getty Brexit: the deciders French President Emmanuel Macron Getty Brexit: the deciders German Chancellor Angela Merkel Reuters Brexit: the deciders Commission President Jean-Claude Juncker EPA Brexit: the deciders The European Parliament's chief Brexit negotiator Guy Verhofstadt Getty Brexit: the deciders Britain's Prime Minister Theresa May Getty Images Brexit: the deciders Britain's Chancellor of the Exchequer, Philip Hammond PA Brexit: the deciders After the first and second appointed Brexit secretaries resigned (David Davis and Dominic Raab respectively), Stephen Barclay is currently heading up the position PA

But the fallout has highlighted Ms May's dependence on the DUP, and given her opponents the chance to pressure her over her failure to secure the deal so far.

Labour has called an urgent question in the House of Commons today, giving Sir Keir Starmer another chance to shout about the major problems the Government finds itself in.

Ms May is planning to return to Brussels before the end of the week, as time runs out to persuade leaders of the remaining 27 EU nations "sufficient progress" has been made to move Brexit negotiations on to their second phase.