A number of toilets in the Palace of Westminster have broken ahead of a late-night debate on Brexit.
Loos on the upper floor have been deemed out of action, leading MPs to complain that it will be an “uncomfortable” evening.
House of Commons authorities said the problem had been “identified” but could not say when the toilets would be back in use.
Tory MP Michael Fabricant (Lichfield), writing on social media, said: “Water shock! Late night sitting in the House of Commons tonight and a water shortage has just been declared in the Palace of Westminster.
“Loos are no longer flushing! It could be an uncomfortable few hours.”
A House of Commons spokesman told the Press Association: “It is being investigated at the moment, the problem has been identified and it is being dealt with.
“We don’t have a timetable for when they will be back in use.”
MPs are expected to sit into the early hours of Wednesday morning as they debate Theresa May’s Brexit deal ahead of a Commons vote next week.