A London MP has tabled a motion in the Commons "commending" unions for protesting against job cuts on the Tube ahead of a third strike by workers.
The motion by John McDonnell, Labour MP for Hayes and Harlington, was backed by four of his Labour colleagues.
About 11,000 members of the Transport Salaried Staffs' Association and Rail Maritime and Transport union will strike over plans to cut 800 jobs.
Workers on London Underground will walk out from 1900 GMT.
Passengers face disruptions as maintenance staff start their 24-hour strike. Operational staff will not report for shifts for 24 hours from 2100 GMT.
Union members are opposed to the axing of 800 jobs on the network, which they say will affect station managers and ticket office staff.
Transport for London (TfL) said cuts would have no impact on safety and would not result in compulsory redundancies.
A spokesperson said: "The changes we're proposing to ticket office opening hours are in line with customer demand, so that our employees are deployed in those places and at those times where passengers most value their help and reassurance."
TfL has issued a list of 80 stations of the total 270 stations on the network which will remain closed during the strike.
The list includes Angel, Piccadilly Circus, Heathrow Terminal 4, Fulham Broadway, Marble Arch and Charing Cross.
The union said the list was "pure fantasy" claiming that many stations could be opened "without staff with potentially dire consequences".
But TfL said about 200,000 people viewed the list of closed stations it issued during the last strike in October.
TfL said: "We intend to run well over a third of Tube services once again". Extra buses and river services will also operate during the strike.
The Commons motion, backed by Islington North MP Jeremy Corbyn, Ealing Southall MP Virendra Sharma, Jim Dobbin, MP for Heywood and Middleton, and Luton North MP Kelvin Hopkins, agreed with the unions' proposals for "reasonable and safe staffing levels".
The motion said that it "condemns" job loss proposals and claims London Mayor Boris Johnson "has broken a 2008 campaign pledge to defend local ticket offices and that his proposals have been denounced by a cross-party vote in the London Assembly".
The motion "commends members of the National Union of Rail, Maritime and Transport Workers and the Transport Salaried Staffs' Association, pensioner groups and transport campaigners in seeking to defend the Tube as a vital public service".
It also expressed "worries" that the job losses would lead to increased maintenance problems, reduced safety standards and more delays.
Earlier RMT general secretary Bob Crow said: "All we have been asking is that the London mayor stick to the pledge he made during his election campaign, when he too recognised that people wanted to see stations staffed properly.
"The message is simple: suspend these cuts and we will suspend our action."
Mr Johnson said: "Londoners have shown that they will not be deterred from their daily business by these pointless strikes.
"I hope the RMT and TSSA leaderships will face facts and see that their action achieves nothing aside from depriving their members of another day's pay."
A fourth strike is planned for 29 November.