British Prime Minister Boris Johnson and his dog Dilyn leave a polling station, after voting in London on Thursday, in Britain's general election. Photo: AFP

UK Prime Minister Boris Johnson's government intends to present a bill to parliament on Friday to enable Britain to leave the European Union next month, his spokesman said on Monday. "We plan to start the process before Christmas and will do so in the proper constitutional way in discussion with the speaker [of the House of Commons]," Johnson's spokesman told reporters.

The announcement came as Johnson begins a new week with a fresh mandate to fulfil his promise to push through his election promise to "Get Brexit Done" on January 31.

His gamble to call an early election to give him a majority in parliament to get approval of his divorce deal paid off spectacularly last week.

His governing Conservative Party won 365 seats - a majority of 80 - at the expense of the main opposition Labour Party, which was offering a second referendum on continued membership.

The smaller Liberal Democrats, which wanted to scrap Brexit altogether, also saw its number of MPs fall.

Johnson's spokesman indicated the presentation of the bill could involve a vote by MPs but that would ultimately depend on the speaker.

Britain will enter talks with the bloc from February to thrash out a new trade deal before a formal end to the transition period at the end of December next year. Brussels has indicated that a comprehensive agreement may not be possible in such a short time frame.