There was widespread disruption to London’s Tube network during the previous three walkouts London Underground staff are set to begin a fourth 24-hour strike later on Sunday after negotiations with Tube bosses failed last week.
Members of the RMT and the Transport Salaried Staffs Association (TSSA) will walk out from 1829 GMT.
The unions say cutting around 800 jobs will affect the safety of the service – a claim Transport for London disputes.
It said it would try to run as many trains as it could but most journeys were likely to be disrupted.
There is likely to be further disruption to the travel network on Monday as commuters return to work.
Union members have already staged three strikes in recent months over the job loss threats.
The two sides had met at the conciliation service, Acas, last week to try to avert a walkout, but the talks broke down.
But Transport for London (TfL) claimed that the unions walked away from an offer of a further six weeks to review staffing plans.
The unions countered this and said London Underground management had rejected their proposal to suspend the strikes for 12 weeks while further safety evaluations were carried out over a 12-week period.
The row centres on the future of 800 employees in ticket offices at Underground stations.
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Managers say fewer staff are needed at counters because of the widespread use of Oyster swipe cards.
But the RMT says this will affect both passenger and staff safety.
But Tfl refuted this, saying all stations will be staffed while open.
On its website, TfL has said that volunteers would be on hand at key stations to assist passengers, and an extra 100 buses would be running.
It warned that its cycle hire scheme was likely to face high demand and that some Tube stations would be closed.
It advised people to check before embarking on their journey, but has already said that on Monday, it expected to be able to run trains on all lines except the Circle line – although some sections of lines may have no service.
In Zone One, it expected the Piccadilly and Circle lines to be out of service, while service would start on the Central line from 1000 GMT.
Among the 77 stations already announced as expected to be closed throughout the day are Charing Cross, Clapham Common, Heathrow Terminal 4, Shepherd’s Bush and Piccadilly Circus.
Others could be partially closed, TfL warned.
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