Brexit should be finalised on December 31 after Prime Minister Boris Johnson and European Commission president agreed on Saturday the two sides shared enough common ground to aim for a final settlement.

Britain formally left the European Union at the end of January but remained part of the bloc’s customs union and single market until the end of the year while both sides discussed permanent arrangements.

Closure seems to be essential after years of negotiations but it has raised questions on Britain's future relationship with the European Union.