The European Union accused Britain of playing a "stupid blame game" over Brexit on Tuesday after a Downing Street source said a deal was essentially impossible because German Chancellor Angela Merkel had made unacceptable demands. With just 23 days before the United Kingdom is due to leave the bloc, the future of Brexit remains deeply uncertain as both London and Brussels positioned themselves to avoid blame for a delay or a disorderly no-deal Brexit. In a sign that Johnson's last-ditch proposals to bridge the Brexit impasse have failed, a Downing Street source said Merkel and Johnson spoke on Tuesday morning and she made clear that a deal was "overwhelmingly unlikely". The Downing Street source said that if Merkel's position on Northern Ireland remaining in the EU's customs union was the bloc's position, then a deal was impossible. "If this represents a new established position then it means a deal is essentially impossible not just now but ever," the Downing Street source said. A spokesman for the German chancellor confirmed the call had taken place but declined to comment further. The EU was scathing. "Boris Johnson, what's at stake is not winning some stupid blame game," European Council President Tusk said on Twitter. "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?" Such abrupt remarks indicate the Brexit blame game has begun in earnest, and that now both London and European capitals are preparing for an acrimonious and potentially chaotic Brexit for which neither side wants to be held responsible. Johnson's spokesman said the British leader and Merkel had had a frank exchange and Britain had not seen any compromise from the EU. He said talks were at the critical point and it was not Britain talking about blame games. A disorderly Brexit could rip apart the United Kingdom, endanger the peace in Northern Ireland, hurt global growth and shape the future of the European Union which was built on the World War II ruins of Europe. An array of remarks by unidentified British sources laid bare just how far apart the two sides are after three years of tortuous haggling over the first departure of a sovereign state from the EU. Brexit talks are now reaching a critical moment, a British spokesman said in Brussels where Johnson's Brexit negotiator David Frost was in meetings with EU officials. But Ireland braced for the worst with a no-deal Brexit budget while Britain announced its no-deal tariff plan and updated on it preparations for a no-deal exit — the nightmare scenario for many big businesses. According to a Downing Street source, Merkel said that for a deal, Northern Ireland would have to stay in the EU's customs union and full alignment with the EU forever — demands Johnson could never accept or push through parliament. Arlene Foster, the leader of the Northern Irish Democratic Unionist Party that supports Johnson's government, accused the EU and Ireland of trying to trap the British province in a permanent customs union. A separate Downing Street source told Reuters that unless the European Union compromises and does a Brexit deal shortly, then the United Kingdom will leave without a deal. "If the EU doesn't do a deal shortly, then we leave without a deal," the source said. "We are leaving the European Union." The opposition Labour Party said Johnson was trying to apportion blame ahead of a no-deal Brexit. "This is yet another cynical attempt by Number 10 to sabotage the negotiations," said Keir Starmer, Brexit spokesman for the Labour Party. "His strategy from day one has been for a no-deal Brexit." Johnson has consistently said the United Kingdom will leave the EU on Oct. 31 with or without a deal, though a law passed by parliament demands he write a letter to the EU asking for a delay if he cannot strike an exit deal by Oct. 19. He has said he would abide by the law but Britain would leave the EU by the end of the month, without explaining that contradiction. He has also repeatedly demanded an election but parliament has refused to grant one. Scotland's top court will rule on Wednesday whether to order Johnson to abide by the law forcing a delay and if it could sign a letter asking for an extension if he refuses to do so himself. The Spectator magazine quoted an unidentified source in Downing Street as saying that Britain would take an aggressive stance towards the EU if Brexit talks break down, possibly even by withholding security cooperation. "This government will not negotiate further so any delay would be totally pointless," the source was quoted as saying. "We'll either leave with no deal on 31 October or there will be an election and then we will leave with no deal." — Reuters