European Council President Donald Tusk (left), European Commission President Jean-Claude Juncker and British Prime Minister David Cameron holds a meeting at the Council of the European Union on February 19, 2016 in Brussels, Belgium. | Dan Kitwood/Getty Everything you need to know about overnight EU summit talks

Prime Minister David Cameron left the European Council building in Brussels at 5.30 a.m. Friday morning, without saying how his attempt to reach a deal on Britain's EU membership was progressing.

As Cameron returned around 11 a.m., he said: “We’ve made some progress but there’s still no deal and as I’ve said I’d only do a deal if we get what Britain needs. So we’re going to get back in there, we’re going to do some more work, and I’ll do everything I can."

"It's hard going,” a spokesman for Cameron said early Friday. "Some signs of progress but nothing yet agreed and still a lot to do."

The FT reported that the British prime minister was "visibly frustrated." "I can stay here all weekend if I need to,” the newspaper reported Cameron said. “I won’t go home with an insubstantial deal. We cannot weaken this text.”

What happened last night?

A “working dinner” on Europe's migration crisis turned into a six-hour debate — focused mainly on Austria’s contentious decision to cap the number of asylum-seekers it would take in. After a lengthy discussion EU leaders agreed conclusions on migration (the other topic of this summit) and then swung onto Cameron's negotiation proposals.

Sticking points

'Ever closer union'

Cameron wants treaty change to get Britain out of its commitment to an "ever closer union among the people's of Europe."

“There are those who say it is symbolic, and others who say that symbols matter,” said one EU diplomat. “These are again contortions of language.” Belgium and France are particularly concerned about this, while European Council President Donald Tusk is trying to argue that it does not equate to a commitment for greater political integration.

Migrant benefits

Cameron asked other EU leaders to grant Britain the power to restrict migrants benefits for a period of seven years with the option of extending it twice for two three-year periods. “There was very wide pushback from many others,” a diplomat said. “So — no chance of getting it.”

"The Commission and the Council have defended the importance for it to be as limited as possible," an EU source said.

And will other EU countries, like Austria, be able to adopt a similar "safeguard mechanism" (to limit benefit payments in exceptional cases), which some fear goes against the EU principle of non-discrimination?

As expected, the Visegrád nations -- Poland, Hungary, Slovakia and Czech Republic -- are particularly worried about this.

They've been talking to Tusk and European Commission President Jean-Claude Juncker "about what options we see," said top Czech negotiator Tomáš Prouza.

"Then it was [Tusk and Juncker's] job to negotiate with Cameron -- and some other countries who want to hide behind the U.K. to change parts of their social system."

Financial regulation

France is concerned that British attempts to protect non-eurozone countries in the EU's single market could amount to special treatment for the City of London.

One EU diplomat said Tusk and Juncker's bilateral talks with the French are "progressing" on economic governance concerns, but "still to be confirmed this morning."

Who met who?

Cameron met separately with French President François Hollande, Czech Prime Minister Bohuslav Sobotka and Belgian Prime Minister Charles Michel. Juncker and Tusk then also met those same leaders, who are understood to be trying to insert a "last chance" clause to ensure Britain can not return asking for more changes at a later date.

What the leaders said

European Council President Donald Tusk: “We made some progress but a lot remains to be done.”

German Chancellor Angela Merkel: “It became clear that agreement will not be easy for many, but that the will is there.”

Italian Prime Minister Matteo Renzi: “Some small steps ahead on migration but some steps back on Brexit.”

Irish Taoiseach Enda Kenny channeled Shakespeare: "If it were done when 'tis done, then 'were well it were done quickly." He was the most supportive of Cameron: "You all have your problems but no one has bigger problems than David. He’s got half his cabinet against him, he’s got half his party against him. We have to give him a deal he can take home and sell to the British people."

Lithuanian President Dalia Grybauskaite said: "I think everybody will have his own drama. And then we will agree."

European Commission President Jean-Claude Juncker (before talks got underway Thursday): “I'm quite confident that we will have a deal during this European Council."

U.K. Prime Minister David Cameron: "We’ve made some progress but there’s still no deal and as I’ve said I’d only do a deal if we get what Britain needs."

What's happening this morning?

Tusk and Juncker are talking again with EU heads of state, while the sherpas (top diplomats from EU countries) work on the language of an agreement.

Cameron will speak to Tusk at 11.45 a.m. a spokesperson for Number 10 Downing Street said.

English breakfast, became brunch, became lunch. All 28 EU leaders are planned to gather again at 1.30 p.m. to discuss the latest developments in an English lunch.

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