Talks between Britain and the European Union on a post-Brexit trade deal will continue overnight but London believes the current offer from the EU remains unacceptable, a British government source said on Saturday. British Prime Minister Boris Johnson and European Commission chief Ursula von der Leyen both said on Friday that Britain was likely to complete its journey out of the EU in three weeks without a trade deal. “Talks are continuing overnight, but as things stand the offer on the table from the EU remains unacceptable,” the British source said. “The prime minister will leave no stone unturned in this process, but he is absolutely clear: any agreement must be fair and respect the fundamental position that the UK will be a sovereign nation in three weeks’ time.” The EU and Britain are at loggerheads over fishing rights, economic fair play and dispute settlement despite months of talks to cover trade after Dec. 31, when a transition period that has kept the country in the bloc’s single market and customs union following its January exit comes to an end. The two sides have set a deadline of Sunday to find agreement and prevent a chaotic break.