Tusk: 'Getting closer' to a Brexit deal

Tusk – who has cancelled a trip to the Middle East on Tuesday and Wednesday – will also meet with May, who had lunch with EU Commission president Jean-Claude Juncker to hammer out the final details of a divorce deal.

'Sufficient progress' is the benchmark for EU leaders negotiating the initial issues – of the Irish border, citizens' rights and the financial settlement – to greenlight moving the discussions on to a transition period and future relations, at their summit next week.

Further raising hopes of a deal, Varadkar said he would also make a statement later on Monday.

Varadkar is said to make a "positive statement to the country to provide reassurance on Brexit", deputy prime minister Simon Coveney was quoted by Irish broadcaster RTE.

He added that an agreement on the wording around the issue of a border on the island of Ireland is very close.

Varadkar and Juncker spoke on the phone just before May arrived at the Commission's Berlaymont headquarters.

Neither May nor Juncker spoke to reporters as she arrived.

The key outstanding issue going into Monday has been the border between Northern Ireland and the Republic of Ireland.

The Republic of Ireland has sought guarantees from the UK that there would be no regulatory divergence with Northern Ireland, in order to avoid border checks and a hard border on the island that has seen decades of sectarian violence.

Sources said the UK has agreed to this in principle, but that the compromise language on the 'regulatory divergence' is the key in the joint report that is being prepared by the EU and the UK.

Earlier Juncker met with the MEPs tasked with keeping an eye on the Brexit talks.

Belgian MEP Philippe Lamberts told reporters he was surprised that the UK has agreed to commit to full alignment.

"I was told the UK is prepared to say there will be no divergence," he said.

"It's a recognition of reality, that they [UK] created - and that reality is full of contradictions," Lamberts quipped.

The joint report prepared summarising the progress in Brexit negotiations is a substantial text, which could serve as the outline of the withdrawal agreement.

"I really hope so [that there is a deal today], it is in no-one's s interest to let this drag on," the Green MEP said.

Besides the Irish issue, there have been a few points regarding citizens' rights where negotiators still had work.

European Parliament negotiators said they wanted to see a commitment from the UK that the new application procedure for EU citizens to keep residing in the EU (to obtain a so-called 'settled status') will be inexpensive and simple.

Sources said the UK has agreed to allow welfare benefits to be exported by EU citizens to other countries.

If a deal is agreed on Monday, the EU Commission can recommend to EU leaders to give a green light to transition and trade talks to begin with the UK. EU leaders can sign that off at their summit meeting at the end of next week.