Brussels - British Prime Minister Theresa May has acknowledged that Brexit negotiations "still have some way to go" as the leaders of the 27 European Union countries that will remain after Britain's exit on Friday rejected moving on to the next phase of talks.

The 27 EU leaders decided to put off a decision until December on whether sufficient progress has been achieved in the current talks, which would allow them to move on to discussing a future relationship. They noted, however, that the EU 27 would start internal preparations for talks on the next phase.

"Exaggerated reports"

"I am ambitious and positive for Britain's future and for these negotiations, but I know we still have some way to go," May said.

"We must work together to get to an outcome that we can stand behind and that works for all our people."

May also stressed that while she was working towards a "good deal," "it would be irresponsible" not to look at "all eventualities," including the possibility of the talks failing.

"My impression is that the reports of the deadlock between the EU and the UK have been exaggerated," said European Council President Donald Tusk. "While progress is not sufficient, it doesn't mean there is no progress at all."

Strong plea

The EU 27 adopted their conclusions on the state of Brexit talks after a last-ditch effort by May to convince them to move negotiations on to the next phase seems to have fallen on deaf ears.

May made a strong plea over dinner on Thursday for the EU leaders to green-light moving on to talks about Britain's future relationship with the bloc, despite the fact that key issues on Britain's departure, which include questions over citizen's rights, the Irish border and a financial settlement, remain unresolved.

German Chancellor Angela Merkel said the issue of Britain's financial commitments is the key to beginning trade talks.

She said considering the intensive, interwoven character of relations between Britain and the EU, there were many aspects to consider with regards to a future relationship between the two sides.

"It was her best performance yet – in the sense that it conveyed a warm, candid and sincere appeal that she wants progress to be made, that she has moved in her position – so I think that was appreciated," said Maltese Prime Minister Joseph Muscat.

"But I believe it hasn't really changed anything from before that."

Call for more details

The leaders of the remaining EU member states called for more details on the British positions, including "a firm and concrete commitment from the UK to settle all" of its remaining financial obligations.

"We have some details, but we do not have all the details we need," European Commission President Jean-Claude Juncker told reporters.

Lithuanian President Dalia Grybauskaite said it was time to "start to negotiate, not only talk."

"We are caged in some kind of a rhetoric negotiations and performance in the media," she said. "It's time to go down and to start real negotiations."