Firefighters are to stage two eight-hour strikes in the capital in a row over new contracts, it has been announced.
Members of the Fire Brigades Union in London will walk out from 10am on October 23 and November 1 after voting by 79% in favour of a campaign of strikes.
The union had given London Fire Brigade until Friday to withdraw letters it said effectively sacked firefighters, to be re-employed on worse terms.
FBU general secretary Matt Wrack said: "Firefighters hate going on strike, but they hate being bullied even more. The London Fire Brigade needs to lift the sacking notices and start negotiating properly."
London firefighters have been taking action short of a strike, including an overtime ban, since last month. The fire brigade is proposing to change the start and finish times of duty for its frontline firefighters by reducing the current 15-hour night shift to 12 hours, and increasing the current nine-hour day shift to 12 hours, providing a longer day shift.
The brigade insists firefighters will continue to work two day shifts followed by two night shifts and then have four days off.
A spokesman said: "The current start and finish times have been in place since 1979 and the work we do today has changed dramatically. We don't just respond to fires any more. Firefighters train for and attend a much wider range of incidents such as flooding, collapsed buildings, chemical incidents etc, and work harder than ever before to prevent fires from happening in the first place.
"The current start and finish times also result in a change of shift during both the morning and evening rush-hours when fire brigade incident demand is at its highest.
"The changes would significantly increase the productive time available during the day shift for essential training and community fire safety work to be arranged. For instance, firefighters now prevent fires by visiting Londoners in their homes, fitting free smoke alarms and offering advice on preventing fires.
"The new start and finish times would also mean less disruption to services during a crucially busy period of the day. The current shift change takes place during morning and evening rush-hour."