Speaker John Bercow has given the Government until the end of the day to publish 58 'secret' studies examining the economic impact of Brexit.
MPs backed an obscure parliamentary motion last week demanding David Davis' department publish the assessments into how the EU withdrawal will impact on sectors ranging from tourism to pharmaceuticals, which make up nearly 88 per cent of the economy.
Mr Bercow, speaking last night, said MPs needed a response "very promptly indeed", adding: "Failing that, I expect ministers to explain to the House before we rise tomorrow evening [Tuesday] why they have not provided them and when they propose to do so."
Failure to publish the raft of studies has prompted a major political row with more than 170 cross-party MPs urging their release, while campaigners also threatened the Government with legal action if the assessments were not made public.
Shadow Brexit minister Matthew Pennycook raised concern that ministers were not treating the Parliament with the "required respect or seriousness" after the Brexit Secretary said the studies could not did not exist in 58 separate documents.
Mr Davis wrote to Hilary Benn, chair of the Brexit select committee, saying "it is not the case that 58 sectoral impact assessments exist" and analysis was "constantly evolving and being updated based on our regular discussions with industry and our negotiations with the EU".
He said: "But it is not, nor has it ever been, a series of discrete impact assessments examining the quantitative impact of Brexit on these sectors."
Ministers have argued that publishing the studies would undermine the UK negotiating position but critics claim the information is being hidden out of fear the findings might embarrass the Government.
Officials previously turned down freedom of information requests from Labour MP Seema Malhotra to publish key details from the studies, saying the negotiations need to be conducted in a "safe space".
It comes after MPs approved a Labour motion, which asked for a “humble address” requesting the Queen to direct Mr Davis to release the impact assessments.
There was confusion during the debate about whether a vote triggered would be binding but the Brexit department later indicated it would comply with the request.