Five former government ministers to be called by Grenfell Tower Inquiry

Mr Pickles, Mr Barwell and Mr Wharton have all been made Conservative peers since the Grenfell Tower fire, while Mr Lewis remains in government as Northern Ireland secretary. He served as chair of the Conservative Party under Theresa May.

All five ministers held roles which carried some responsibility for acting on the recommendations made by Francis Kirkham, the coroner who investigated the six deaths at Lakanal House in 2013.

In March 2013 she had sent then-secretary of state Mr Pickles a series of recommendations, including that the government should review building regulations guidance “with particular regard to the spread of fire over the external envelope of the building” and encourage the retrofitting of sprinklers in social housing.

But the government pushed this review back to 2017 and did nothing to mandate the retrofitting of sprinklers.

Inside Housing has previously revealed a series of letters sent to all of these ministers, with the exception of Mr Lewis, by an all-party parliamentary group urging them to act more quickly on the recommendations.

In response to one letter, sent in September 2015, Liberal Democrat Mr Williams wrote: “I have neither seen nor heard anything that would suggest consideration of these specific potential changes is urgent and I am not willing to disrupt the work of this department by asking that these matters be brought forward.”

Mr Lewis meanwhile responded to questions about why the government had not introduced a requirement for sprinklers in tower blocks in 2014 by citing “our commitment to be the first government to reduce regulation”.

Sir Ken was a key advisor to the government on fire safety before Grenfell and authored a report for it after the Lakanal House fire, which said retrofitting sprinklers in high rises would not be “practical or economically viable”.

A string of officials who worked at the Department for Communities and Local Government (since rebranded as a ministry) in this period will also face questioning.

This includes Brian Martin, the official responsible for official guidance covering cladding systems contained in Approved Document B. He continues to hold a senior role at the ministry.

It will also hear from Melanie Dawes, permanent secretary at the ministry until February 2020, when she left to take up a role as chief executive of broadcasting regulator Ofcom.

The letter was sent to core participants on Monday and said module six – where the actions of central government will be investigated – is currently projected to begin on 18 October.

It will be divided into four broad areas: firefighting, fire risk assessments, testing and certification, and the government.

The module on the government will consider, among other things, the development and interpretation of its building regulations and guidance, government policy on fire safety and the evidential basis for it.

The firefighting section will consider, among other issues, “lessons arising from the Lakanal House fire and other relevant fires in the UK and abroad”, the letter said.

It will also see Danielle Cotton, former commissioner of the London Fire Brigade, recalled to give evidence. Ms Cotton upset survivors in the first phase when she said she would change nothing about the London Fire Brigade’s response and compared the fire to a “space shuttle landing on the Shard”.

The section on fire risk assessments will focus on what steps were taken to address recommendations made by Ms Kirkham “in respect of clarifying the scope of fire risk assessments and the training and competence of fire risk assessors”.

The testing and certification section will cover a range of topics surrounding the regulation of cladding systems and their testing and will see witnesses from Celotex, Kingspan and testing house the Building Research Establishment called.

This follows on from the appearance of witnesses from these organisations in module two, which examined the same topic but with a specific focus on the materials used on Grenfell Tower.

A full list of the witnesses announced by the inquiry in the letter is below: