Boris Johnson is threatening to withhold 30 billion pounds ($A55 billion) from the Brexit divorce bill unless EU leaders agree to amendments to the deal.
British Prime Minister Boris Johnson will tell European Union leaders he will withhold 30 billion pounds ($A55 billion) from the Brexit divorce bill unless they agree to changes to the deal, the Mail on Sunday has reported.
If Britain leaves the bloc without a trade deal, lawyers have concluded the government will only have to pay the nine billion pounds ($A16 billion), rather than 39 billion pounds ($A71 billion), the newspaper reported.
This is because there will not be any of the costs associated with any transition period, the newspaper said.
Johnson's office did not immediately respond to a request for comment.
Meanwhile Johnson has asked his attorney general whether parliament can be shut down for five weeks from September 9 in what appears to be an attempt to stop MPs forcing a further extension to Brexit, The Observer reported.
An email from senior government advisers to an adviser in Johnson's office written in the last ten days says the prime minister recently requested guidance on the legality of such a move, known as proroguing, the newspaper said.
The legal guidance given in the email is that shutting parliament may well be possible, unless the courts agree to demands by anti-Brexit campaigners to block such a move, the Observer reported.
"The claim that the government is considering proroguing parliament in September in order to stop MPs debating Brexit is entirely false," a government spokesman said.