The Theresa May government suffered a severe blow on Tuesday when it lost a parliamentary vote on legal advice it received on the Brexit deal agreed with EU leaders last month.
A motion moved by opposition Labour Party accusing the government of contempt of parliament by failing to publish the legal advice it received on Britain’s exit from the European union was passed with 311 MPs in favour and 293 against.
The opposition believes the advice will reveal Attorney General Geoffrey Cox's misgivings about the Brexit agreement.
"This House has now spoken and it's of huge constitutional and political significance. It is, I think unprecedented for this House to find government ministers in contempt," Labour's Brexit spokesman Keir Starmer said.
The government, however, agreed to publish the "final and full" advice.
The voting delayed a speech by Prime Minister Theresa May at the start of five days of debate on the deal before a final vote on 11 December which the government is widely expected to lose.
May will address parliament later today as well.
The seizure of initiative by Parliament on Tuesday night is considered as repatriation of power long held by political parties on the power of promises and bluff in public.
Now the House of Commons is taking back control where May’s fragile administration is suffering successive defeats.
Perhaps the more significant legislative event might prove to be the vote for Dominic Grieve’s amendment. Grieve, a former attorney general, now a leading pro-European Tory backbencher, won a concession asserting that the provisions of standing order 24B should not apply to any motion pursuant to section 13 of the 2018 European Union (withdrawal) Act. This amendment beefs up the power of the Commons in the event that May’s deal is beaten and the government cannot get another deal through Parliament. But it does altogether eliminate the risk of a Brexit without a deal.