The Prime Minister failed – five times – to guarantee the vote would be on a Bill, allowing it to be amended, or for her to be sent back to Brussels to seek better terms if her deal is rejected.
Instead, Ms May appeared to suggest it would remain what was dubbed a “take it or leave it” vote, allowing the Government to press head with Brexit – even if MPs object.
Asked by Labour MP Yvette Cooper to confirm there would be a “vote on a statute” (on legislation), she said only that there would be an “opportunity to vote on the deal”.
The choice of words immediately provoked suspicions that the Government will seek to strike out the “meaningful vote”, at a later stage of the EU Withdrawal Bill next month.
Ms Cooper told The Independent: “The Prime Minister wriggled out of giving a straight answer and appears also to be trying to wriggle out of Amendment 7. That’s not on.
“The Prime Minister still obviously doesn’t want the statute until after the deal has been ratified. She cannot keep trying to concentrate power in ministers hands in this way.”
In the Commons, Dominic Grieve – the former Tory Attorney General, who led last week’s revolt – warned ministers that “kicking hornets’ nests is not a very good idea”.
Fellow Labour MP Alison McGovern, supporter of the pro-EU group Open Britain, said: “The language of the amendment was crystal clear: Parliament must be given a real, meaningful vote on the terms of Brexit.
“That means by statute, not just a rubber-stamp of whatever the Government manages to negotiate. It is not acceptable for the Prime Minister to try and ignore the democratically expressed will of our elected MPs.”
And Tom Brake, the Liberal Democrat Brexit spokesman, said: “With all her muddling and obfuscation, it is quite clear that Theresa May is trying to worm her way out of a meaningful vote in Parliament on the Brexit deal.”
Amendment 7, put forward by the highly respected Mr Grieve, was designed to stop the Government using “Henry VIII powers” to enact Brexit by bypassing MPs.
It would prevent the process starting until Parliament has voted in favour of a separate Bill, which could be amended – perhaps to keep the UK in the EU single market and customs union.
Ms May was humbled last Wednesday when 11 Tory MPs joined forces with Opposition parties to defeat her on the controversy, by 309 votes to 305.
But in tense exchanges with Ms Cooper, the Prime Minister repeatedly failed to commit to a vote on a statute, as ordered by the Commons just seven days earlier.
Ms Cooper asked: “Now that Amendment 7 has been passed by Parliament, can you confirm that means there will now be a vote on a statute on the withdrawal agreement before the withdrawal agreement is ratified?”
Speaking to the Commons Liaison Committee, Ms May replied: “It slightly depends what you’re talking about in terms of before.”
And hinting that the vote would in fact be on a “yes-no” motion, she added: “There will be an opportunity for Parliament to vote on that withdrawal agreement before that legislation is brought into place.”
During 45 minutes of questioning on Brexit, the Prime Minister also:
* Insisted she was “confident” she could complete a free-trade agreement with the EU before March 2019 – despite widespread scepticism.
Hilary Benn, the Brexit committee chairman told her: “I’ve met nobody who think it will be possible to negotiate all of the details of that trade deal by March 2019.”
* Refused to say what goods would be covered by her commitment to “full alignment with EU rules” to prevent a hard Irish border – or in what areas the UK would be free to “diverge”.
Ms May said she did not believe that full alignment would be necessary, describing it as a “default default position”, at one point.
* Refused to rule out cameras at the Northern Ireland border, saying: “We are not going to give a running commentary on every detail of our negotiations.”
* Dismissed suggestions of increased trade barriers with either the EU, or the countries with which the EU has trade agreements – suggesting those latter deals could be “rolled over”.
* Denied the UK will be forced to leave Europol and EU arrest warrant – which Brussels has argued – claiming the issue was “part of the negotiations”.
* Denied she was losing out in the negotiations by “begging” for a transitional deal, telling the committee: “I haven’t begged the European Union for two more years.”
Earlier at Prime Minister’s Questions, she conceded Brexit could be delayed until after March 2019, but insisted it would only be “in exceptional circumstances for the shortest possible time”.
Ms May confirmed the Government would support an amendment allowing MPs to put back the exit date if the Brexit negotiations run into trouble.
But she tried to head off unease on the Tory benches by insisting: “We’re very clear we will be leaving the EU on March 29 2019 at 11pm.”
Her comments came as the European Commission said it wanted the planned Brexit transition period to end no later than 31 December 2020.
“The transitional arrangements should apply as from the date of entry into force of the Withdrawal Agreement and should not last beyond 31 December 2020,” its latest negotiating directives said.
The deadline coincides with the end of the EU’s seven-year budget period – but appears earlier than the Prime Minister’s requested transition of “around two years”.
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