Attorney General Geoffrey Cox told opposition MPs to "grow up and get real" because the full Brexit legal advice has been withheld to “guard the public interest” during a heated row in the House of Commons.
Opposition parties in the Commons - including Theresa May's DUP allies - have today written a joint letter to Speaker John Bercow urging him to launch contempt of Parliament proceedings over the issue.
It comes after MPs voted last month to require the government to publish "any legal advice in full".
They said a 43-page summary and a statement by Mr Cox had failed to meet the terms of the vote.
However Mr Cox launched into an angry tirade on Monday, telling MPs: “In this case… to disclose any advice that might have been given would be fundamentally contrary to the interests of this country.
“It’s no use the baying and shouting of members opposite,” he continued. “What I am trying to do is guard the public interest. That’s all.”
The letter to Mr Bercow has been signed by shadow Brexit secretary Sir Keir Starmer, DUP Westminster leader Nigel Dodds and senior MPs from the SNP, Liberal Democrats, Plaid Cymru and Green Party.
Sir Keir tweeted: "The government has failed to publish the Attorney General's full and final legal advice to the Cabinet, as ordered by Parliament.
"We have therefore been left with no option but to write to the Speaker of the House of Commons to ask him to launch proceedings of contempt."
At a rowdy session of parliament, Mr Cox outlined the legal advice, including over a "backstop" arrangement to prevent the return of a hard border between Northern Ireland and EU member state Ireland if a future UK-EU trading deal is not reached in time.
"This deal ... is the best way I firmly believe of ensuring that we leave the European Union on March 29," Mr Cox said. "This is the deal that will ensure that happening in an orderly way with legal certainty."
However many Brexit supporters fear the so-called backstop for Northern Ireland risks tying Britain into the EU's customs union indefinitely.
"The legal summary document is worse than we feared: the backstop customs union is indefinite, the UK would be a rule taker and the European Court (of Justice) is in charge of our destiny, rather than the sovereign UK parliament," former Brexit minister David Davis said. "This is not Brexit."
The DUP, which props up Mrs May's minority government, went further.
Deputy leader Mr Dodds said: "The overall context of this is ... a deeply unattractive, unsatisfactory presentation and he (Cox) needs to therefore rather than recommend this agreement, recommend that it is rejected."
It came as Mrs May told Tory MPs to "hold their nerve" and back her Brexit deal, insisting she would still have a job in two weeks' time as she faces a crunch December 11 Commons vote on her EU Withdrawal Agreement.
