Commons staff will not be left out of pocket, while the government is accused of “staggering from one week to the next”.
MPs have had their February break from parliament cancelled, amid concerns about how prepared the UK is for Brexit on 29 March.
Parliament was due to break up in a fortnight, but Commons Leader Andrea Leadsom announced there were “no plans” to implement the technical measures to do so.
She said she was “very sorry for the inconvenience” and that staff working in parliament will not be left “out of pocket”.
“I do think our constituents will expect that the house is able to continue to make progress at this important time,” Ms Leadsom added.
Valerie Vaz, Labour’s shadow Commons leader, accused the government of “staggering from one week to the next”.
She pointed out that six important pieces of law need to pass in parliament before Brexit day – on immigration, trade, financial services, agriculture, fisheries and healthcare.
Ms Leadsom said she was “confident” all the relevant legislation would be completed on time.
Hours earlier, Foreign Secretary Jeremy Hunt told the BBC that Brexit could have to be delayed because “we might need some extra time to pass critical legislation”.
Jonathan Edwards, a Plaid Cyrmu MP, told Sky News that parliament had to continue to sit but not just to “give the government more time to chase unicorns”.
“Westminster has kicked the can down the road so many times, can-kicking should become the new national sport,” he added.
The UK is due to leave the EU by default at 11pm on 29 March 2019.
Prime Minister Theresa May is struggling to get her deal through parliament, meaning Britain could leave the bloc without an agreement.
