Under the terms of that deal, Britain would continue to follow EU rules after it has left the bloc until the end of 2020 to allow time for the two sides to reach a long-term free trade deal.
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Gauke is among many MPs concerned that it would be difficult to complete the negotiations to such a tight timetable, and that it risked opening a second “trapdoor” to a no-deal Brexit if the UK and EU were unable to reach an agreement in time.
He backed the PM’s Brexit deal and the timetable for passing it through parliament, which ultimately failed, after Buckland made his commitment.
Responding to No.10’s comments, Gauke said: “It was a clear promise.
“As Robert Buckland said ‘parliament has a legitimate role to play’. I agree.
“Looks like the Conservative message is ‘we’ll be out on WTO (no deal) terms by 2021’.
“I have to say – that is reckless.”
Another former Tory, Nick Boles, claimed Johnson withdrew his Brexit deal and plumped for a general election because he knew MPs would pass an amendment to ensure they got a vote on extending the transition.