Theresa May in race against time to secure Brexit deal before Sunday after Gibraltar and fishing deadlock

Theresa May will head back to Brussels on Saturday in a desperate bid to secure a Brexit deal after her latest attempt to win the approval of individual EU states failed.

The Prime Minister announced the unscheduled trip - which will come just 24 hours before a special EU summit to sign off a deal - following an hour-long discussion with European Commission president Jean-Claude Juncker in the Belgian capital.

Downing Street insisted the last-ditch meeting, which is aimed at finall thrashing out details of the UK and EU's future relationship, did not signal “major problems”, but key issues remain outstanding with a number of member states.

German Chancellor Angela Merkel has even threatened to boycott Sunday's crucial summit of EU leaders if the deal is not ready to be signed off by the weekend.

Spain has concerns about the wording over the future status of Gibraltar, while the French, Dutch and Danish governments want better access to British waters for their fishing fleets.

After last night's talks with Mr Juncker and EU officials, May admitted there was still work to do to finalise the deal.

“We've made further progress and as a result we have given sufficient direction to our negotiators, I hope, for them to resolve the remaining issues and that work will start immediately,” she said.

“I now plan to return for further meetings on Saturday to discuss how we can bring to a conclusion this process and bring it to a conclusion in the interests of all our people.”

May also spoke to Spanish prime minister Pedro Sánchez, who wants any future trade deals between the UK and EU not to cover Gibraltar without the approval of Madrid.

Downing Street said the phone call had been a “good engagement” and that Mrs May “looked forward to these discussions continuing as we discuss the future relationship”.

Meanwhile, the full extent of Cabinet disquiet over Mrs May's deal has been revealed by the Daily Telegraph.

According to the paper, Foreign Secretary Jeremy Hunt called it a "Turkey trap", a reference to that country's 31-year long negotiations with the EU over its status.

Others to criticise the draft agreement included Penny Mordaunt, Andrea Leadsom, Sajid Javid and Geoffrey Cox, who said it was an "ugly sister of a deal", and compared it to "two oil drums lashed together in a plastic sail".