Travellers are being advised to avoid using the tube network ahead of planned strikes tomorrow.
Members of the Rail, Maritime and Transport union (RMT) are due to walk out for 24 hours over proposals for 600 job losses, changes to working agreements and pensions.
Transport for London has proposed not replacing up to 600 posts when they become vacant as part of plans to achieve financial sustainability.
But the organisation said no proposals had currently been tabled on pensions or terms and conditions, and nobody would lose their jobs.
Commuters were being warned of "severe disruption" from Monday at 8am for 24 hours.
Many stations will be closed and others might only operate for limited periods.
Services, including DLR, London Overground and Trams, are not affected by the industrial action but could be busier than normal.
Andy Lord, TfL's chief operating officer, said: "I'd like to apologise to London for the impact this strike will have on journeys.
"We know it's going to be damaging to London and the economy at a time when public transport is playing a crucial role in the capital's recovery.
"While our focus is always on helping everyone travel around London whenever they want, the expected impact of the RMT's action means we have to advise people to only travel tomorrow if necessary, as many stations may be closed.
"Alternatives to the Tube, including the bus and rail networks, are likely to be much busier than usual."
RMT general secretary, Mick Lynch, said: "We are demanding a direct face-to-face meeting with Mayor Sadiq Khan to sort this mess out."
“There’s no point in our union continuing to sit opposite management representatives who have neither the inclination nor the authority to negotiate a settlement, when the power lies with the Mayor."
What lines will be affected?
All London Underground lines operated by TfL are expected to be affected, including: Bakerloo, Central, Circle, District, Hammersmith & City, Jubilee, Metropolitan, Northern, Piccadilly, Victoria, and Waterloo & City.
The newly opened Elizabeth Line is not affected by the Monday, June 6, tube strike, as it is not technically a Tube line - running on TfL Rail as part of the Crossrail project.
Other TfL services, including the London Overground and Trams, and are rail services, are also not affected by the industrial action and will be running.
However journeys using those services that will remain open during the strike - including those like the Elizabeth Line that stop at many central London Tube stations - are all expected to be heavily impacted and be busier than usual.
