UK lawmakers voted on Monday to oblige the government to publish its impact assessments for a no-deal Brexit.
The motion, which passed by 311 votes to 302, also requires the UK government to publish communications between government officials over their plans to suspend parliament weeks before the Brexit deadline.
The government now has until Wednesday evening to release all correspondence, including informal communications through such channels as Facebook, WhatsApp and Telegram.
Cabinet ministers have opposed the demands, expressing concerns over the scope of the documents that are to be published.
Earlier in the day, the Queen rubber-stamped a bill seeking to block Boris Johnson from taking the country out of the European Union without a deal in place on 31 October. The prime minister said he would defy the instructions.
Johnson, who repeatedly vowed to exit the UK with or without a deal, previously urged legislators to vote for an early election, but opposition parties said they would only back a snap election if no-deal was off the table.
Monday's session becomes the last until the parliament reconvenes on 14 October. Johnson moved to suspend the parliament in late August, giving the lawmakers just two weeks to take action on Brexit ahead of the 31 October deadline.