A strike by Tube workers is to go ahead after the biggest rail union, the RMT, walked out of talks.
The 24-hour action from 18:00 GMT on Sunday is expected to cause mass station closures.
Both the TSSA and London Underground (LU) remain in talks at the conciliation service Acas.
The strike is organised in protest at plans to close ticket offices. LU has warned travellers to expect major disruption to services.
In a message to RMT members, regional organiser John Leach made it clear the talks had “failed” and the strike by his members would go ahead.