The Fire Brigades Union (FBU) has announced its members have voted in favour of industrial action.
More than three quarters (15,758 of 18,446) of the national union's members voted for a strike to take place but have not yet announced when the action will take place and which sectors of the fire service will be affected.
London Fire commissioner, Ron Dobson, said: "I hope that despite the result of the ballot for industrial action short of a strike, the FBU and government can reach a resolution.
"My priority, as ever, remains the safety of Londoners and I will ensure that London has the fire cover it needs at all times and that disruption is kept to a minimum.”
The Brigade has confirmed its contingency fire service, consisting of 27 fire engines, remains available should further strike action be announced.