David Cameron and European Council President Donald Tusk are set for a “crucial” day of talks about the UK’s renegotiated membership of the EU.
A meeting on Sunday night ended without a deal, though a Downing Street source said there had been a “breakthrough” on restricting benefits for EU migrants.
Tusk said “intensive work” would be needed during the coming hours.
The aim is to agree a deal to be put to EU leaders ahead of a summit on 18 and 19 February.
An early deal would allow Cameron to call a referendum on the UK’s EU membership before the school summer holidays.
After their meeting over dinner on Sunday night, Cameron tweeted that Tusk had agreed to another 24 hours of talks before publishing the UK’s draft renegotiation text, reports the BBC.
Tusk, whose council is comprised of the leaders of other EU states, tweeted: “No deal yet. Intensive work in next 24 crucial. #UKinEU”.
After the 24-hour period has passed, negotiators will decide whether to table a draft agreement or not.
As part of his attempts to renegotiate the UK’s EU membership, Cameron has proposed denying in-work benefits to all EU migrants until they had been in the UK for four years.
He said stopping those migrants from claiming tax credits – income supplements paid to those in low-paid work – would reduce high levels of immigration to the UK.
EU leaders rejected this idea but suggested an “emergency brake” which the UK could use for up to four years.
The UK could use this to deny in-work benefits to EU migrants, but it would have to prove public services were under excessive strain and would need the approval of other EU states.
The proposal was to allow the UK to be able to impose the brake within three months of applying for it, but Cameron wants it triggered immediately after the EU referendum. He also says there should be no time limit on its use.