Autumn response times to fires in Tower Hamlets could suffer due to an escalating row about shift patterns between London fire service authorities and the Fire Brigades Union (FBU).

On Friday The FBU will ballot members on industrial measures, including a ban on overtime, to begin on Friday, September 24.

One East London firefighter, who attended last week’s fire above the Salmon & Ball pub in Bethnal Green, said that unofficial action had begun already.

He told the Advertiser: “Motivation has really gone out the window. The mood’s not good in my station and most people are already refusing pre-arranged overtime.

Union officials claim the overtime ban will expose staff shortages across London stations, hitting incident response times.

The ballot is in response to preparations to terminate the contracts of up to 6,000 firefighters and offer new ones instead.

Firefighters who refused the new terms would be sacked.

Fire Brigade management is proposing 12-hour day, 12-hour night shifts to free up time for community safety work and allow staff to avoid rush-hour travel associated with the present 9am to 6pm system.

The FBU, however, fears the measures are merely a smokescreen for future job cuts.

Ian Leahair, the FBU’s senior London official, said: “This is not about efficiency; it’s about slashing the fire brigade in London.”

There are also concerns that a 12-hour day would deny firefighters time to spend with their families.

Mr Leahair said the union had offered to look at a 10-hour day and also proposed earlier starts and finishes to avoid peak commuting times.

A Fire Brigade spokesman said the proposed shift changes were “not set in stone” and that negotiations with staff representatives were ongoing.

If industrial action does go ahead, the Fire Brigade promises to have cover in place and says it will respond to incidents as normal.