Prime Minister Boris Johnson is set to tell German Chancellor Angela Merkel on Wednesday that unless she agrees to change the Brexit deal, Britain will leave the European Union on Oct. 31 without a deal.

More than three years after the United Kingdom voted to leave the EU, it is still unclear on what terms - or indeed whether - the bloc’s second largest economy will leave the club it joined in 1973.

Johnson, a Brexiteer who won the premiership a month ago, is betting that the threat of ‘no-deal’ Brexit turmoil will convince Merkel and French President Emmanuel Macron that the EU should do a last-minute divorce deal to suit his demands.

But with just over 10 weeks left until the United Kingdom is due to leave, the EU has repeatedly said it will not renegotiate the Withdrawal Agreement struck by Johnson’s predecessor, Theresa May, and that it will stand behind member state Ireland.

Merkel on Tuesday said she was open to “practical solutions” to the Irish border insurance policy or ‘backstop’ that Johnson says is unacceptable - but that the Withdrawal Agreement was not to be reopened.