Boris Johnson will face a Commons showdown today as he tries to push through his controversial Brexit deal against significant opposition.
Speaker John Bercow is set to rule on whether the Government can bring a so-called “meaningful vote” on its plans.
If the Speaker blocks the move, focus will switch to the Government bringing its Withdrawal Agreement Bill (WAB) before MPs on Monday, with a vote on its second reading on Tuesday.
Ministers insist they “have the numbers” to push the agreement through, but the parliamentary situation appears to be on a tightrope.
Labour has made clear it will try to hijack the legislation by putting down amendments for a second Brexit referendum and a customs union with the EU.
Shadow Brexit secretary Sir Keir Starmer indicated Labour could even back the WAB if it was put to voters in a national poll against a Remain option.
Shadow solicitor general Nick Thomas-Symonds said that Labour MPs will call for a confirmatory referendum, adding that he thought Parliament may vote in favour of Britain staying in a customs union with the bloc.
“A customs union is going to be one of the amendments that comes through and that is something that is going to have a very good chance of getting a majority,” Mr Thomas-Symonds told BBC Radio 4’s The Westminster Hour.
But, in a column for The Daily Telegraph, International Trade Secretary Liz Truss said making a customs union part of any pact “would take us back to square one and render the UK unable to strike our own bilateral trade agreements around the world”.
Despite being forced by Parliament to request a Brexit delay from Brussels after another embarrassing Commons defeat on Saturday, Mr Johnson and Ministers are talking up their chances of rushing Brexit legislation through.
The move came amid reports that the EU was considering offering the UK a “flexible extension” to February, allowing it to leave whenever an agreement is secured.
The PM is striking a bullish stance as he faces another rollercoaster week in the Commons, insisting the UK will still quit the EU in 10 days.
He abandoned plans for a meaningful vote on a Saturday sitting of the Commons after suffering an embarrassing defeat at the hands of former Tory minister Sir Oliver Letwin.
But the PM had not suffered a loss but achieved a “boost to his strategy”, according to former Tory leader Iain Duncan Smith.
“For every time he is forced to take a defiant stand against the Remainers in Parliament, it only becomes clearer to the British public just who is fighting desperately and against the odds to deliver their wishes, and who is to blame for the fact that Brexit is not yet over,” Mr Duncan Smith wrote in The Daily Telegraph.
After losing the vote, Mr Johnson had no option but to write to European Council president Donald Tusk, as Parliament demanded, requesting a three-month extension to the end of January.
The PM did not sign the letter, and sent a second communication insisting that a delay would be “deeply corrosive” for the UK and the EU.
Labour accused Mr Johnson of behaving like a “spoiled brat”.
The DUP was reported to be considering backing Labour’s move to force a new customs union with the EU into WAB legislation.
Commons Leader Jacob Rees-Mogg told MPs the Government aimed to hold a meaningful vote on the Brexit deal on Monday.
Mr Bercow said he would consider whether to allow the Government’s plans, but he could rule that such a vote effectively happened on Saturday and cannot be repeated so soon.
However, party chief whip Sir Jeffrey Donaldson told BBC Radio 5 Live he wanted to engage with the Government to see “where things stand”.
If the PM’s deal is amended he will have no choice but to accept a long delay to the UK’s departure from the bloc.
A Government source said: “Parliament needs a straight up-and-down vote on the deal… or do they want to frustrate and cancel Brexit altogether?
“We cannot allow Parliament’s letter to lead to Parliament’s delay.”
The source said the WAB would need more late-night and weekend sittings by MPs.
Related: Protester credited for “brilliant demolition” of arguments against confirmatory referendum
