Concerns have been raised about the so-called "stay put" policy under which residents were told to remain in their flats. (PA)

Britain’s firefighters still don’t know how to evacuate tower blocks two years after the Grenfell disaster, a union has claimed.

Matt Wrack, the general secretary of the Fire Brigades Union (FBU), has criticised the lack of policy change in the wake of the June 2017 tragedy, in which 72 people lost their lives.

Mr Wrack told The Telegraph that individual firefighting authorities had been left alone to explore how to improve training for high-rise evacuations, but so far only Greater Manchester had taken any action.

The fire chief said “nothing much” had been done to improve training and there remains no national body to assess and implement the lessons learnt from Grenfell.

View photos The Grenfell inquiry's report is set to be published later this month. (Reuters) More

He added that an upcoming report from the Grenfell Tower public inquiry, which is set to be released this month, had been used to justify a lack of action.

“It just seems to be a process of kicking the can down the road, an excuse for Government to do nothing - and nothing significant has happened in the past two and a half years,” Mr Wrack said.

“We were promised change, I haven’t seen any change.”

During the deadly inferno, the majority of Grenfell residents were initially told by 999 operators to remain in their flats and a full evacuation was only ordered after two hours.

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But Mr Wrack criticised the so-called “stay put” policy, and said lives are being put at risk while the procedure remains the default stance of firefighters attending high-rise blazes.

“With stay-put, why would you sit back and wait for three years before doing something?” Mr Wrack added.

“Is the inquiry able to say what the answer to stay-put is, or is it going to say ‘someone needs to do something about stay-put’?

"At which stage you ask, 'why couldn’t you have done that within six months of the fire?'."

Many high-rise buildings, including Grenfell Tower, were designed so that fires could be contained within a single accomodation unit, negating the need for a full evacuation.

But design flaws exposed since the disaster have shown that advising people to remain in their flats could potentially prove fatal.

Mr Wrack admitted he was “sceptical” that an evacuation policy would work better than stay-put but said “something needs to be done” to investigate a new procedure.

On Friday this week, the families of those killed in the Grenfell Tower blaze said they feared the report will be “buried in Brexit” after it was revealed that it will be published a day before Britain is due to leave the European Union.

Prime Minister Boris Johnson, in a letter to inquiry chairman Sir Martin Moore-Bick, set a deadline of October 30 for making public the initial findings on the west London fire.

“To publish the report on October 30 risks burying it in Brexit,” Natasha Elcock, chairwoman of bereaved families’ group Grenfell United said in a letter to inquiry chairman Sir Martin Moore-Bick.

“There has been no consultation with any survivors and bereaved families around the date of publication,” said Ms Elcock.

“This is not the first time we have had to question whether bereaved families and survivors are really at the heart of this inquiry.”

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