Fears of no-deal Brexit raised again as Boris Johnson legislates to end transition period in 2020

Ministers are understood to have re-worked the Withdrawal Agreement Bill (WAB) – due to come before the Commons this week – to “legally prohibit” any further extension.

The move comes as MPs gather at Westminster for the first sitting of the new parliament following the general election.

Under current plans, the government intends to end Britain’s EU membership on January 31, with an implementation to run to the end of 2020 while it negotiates a free trade agreement with Brussels.

However key EU figures – including chief negotiator Michel Barnier – have expressed scepticism a deal can be agreed in time, raising the fresh prospect of a no-deal break unless there is an extension.

A No 10 source said: “Last week the public voted for a government that would get Brexit done and move this country forward – and that’s exactly what we intend to do starting this week.

“Our manifesto made clear that we will not extend the implementation period and the new Withdrawal Agreement Bill will legally prohibit the government agreeing to any extension.”

The prime minister repeatedly promised during the election campaign that he would not seek any extension to the transition period.

The commitment was instrumental in persuading Nigel Farage not to stand Brexit Party candidates in Conservative held seats.

However, after Johnson was returned with an unexpectedly large majority, there was speculation he could use his strengthened position to seek an extension if more time was needed to get a trade deal.

The WAB is due to be brought before the Commons on Friday – and could receive its first reading and be voted on at second reading in one day, if the speaker agrees.

The prime minister’s official spokesman said: “We plan to start the process before Christmas and will do so in the proper constitutional way in discussion with the speaker.”