The UK government has reportedly accused German Chancellor Angela Merkel of telling Prime Minister Boris Johnson that a Brexit deal is “overwhelmingly unlikely” unless London accepts new conditions.

A Downing Street source said Mrs Merkel had “made clear she thinks the EU has a veto on Britain leaving the customs union,” Sky News and the BBC have reported.

A No.10 spokesperson confirmed that it had given a read-out of the phone call but would not immediately share it.

In Berlin, the German government confirmed that the call took place but declined to give details of the “confidential conversation.”

Both broadcasters quoted Downing Street as saying Mrs Merkel’s comments make a deal “essentially impossible.”

Keir Starmer, the UK opposition Labour party’s Brexit spokesman, accused Johnson’s Conservative government of trying to “sabotage the negotiations” through its remarks on the phone call.

In Brussels, European Council President Donald Tusk tweeted to Johnson that “what’s at stake is not winning some stupid blame game.”

“At stake is the future of Europe and the UK as well as the security and interests of our people,” Mr Tusk wrote.

“You don’t want a deal, you don’t want an extension, you don’t want to revoke, quo vadis?,” he added, using the Latin for “Where are you going?”

.@BorisJohnson, what’s at stake is not winning some stupid blame game. At stake is the future of Europe and the UK as well as the security and interests of our people. You don’t want a deal, you don’t want an extension, you don’t want to revoke, quo vadis?

— Donald Tusk (@eucopresident) October 8, 2019

European Commission spokeswoman Mina Andreeva stressed that the Brussels is still “working for a deal” and technical talks are continuing.

But pro-EU Labour MP Hillary Benn, who instigated new legislation designed to prevent Johnson taking Britain out of the EU without a deal on October 31, said the Downing Street statement was “about blaming Angela Merkel for something that is from Boris Johnson.”

Johnson met European Parliament President David Sassoli in London late on Tuesday, after Sassoli held closed talks with Merkel in Berlin earlier.

However, Mr Sassoli said that while he had entered Number 10 hoping to hear proposals that could take negotiations forward, he left disappointed. “I must note that there has been no progress,” he said.

Johnson also spoke to Irish Prime Minister Leo Varadkar by phone late on Tuesday, with the duo agreeing to meet this week, Irish national broadcaster RTE reported.

“Both sides strongly reiterated their desire to reach a Brexit deal,” RTE quoted a government spokesperson as saying.

Irish Foreign Minister Simon Coveney earlier tweeted that it was “hard to disagree” with Mr Tusk’s statement, which “reflects the frustration across EU and the enormity of what’s at stake for us all.”

Mr Johnson has insisted that Britain must leave the EU on October 31, with or without an exit deal.

-AAP