Lord Greenhalgh stepped down Friday saying he was ‘saddened’ by events which led to prime minister’s downfall

The government’s minister for building safety and fire safety has stepped down following Boris Johnson’s announcement that he would leave Number 10.

Lord Greenhalgh published his resignation letter on Friday afternoon after a speech by the prime minister, in which he accepted the need for a new leader while appearing to blame the “herd instinct” of Conservative MPs for his downfall.

The lord has been a major force behind the government’s Building Safety Act, which is set to overhaul the building safety regulatory framework and provide new protections to leaseholders.

Stephen Greenhalgh

Lord Stephen Greenhalgh

The former minister had talked tough with the housebuilding industry, promising to sanction them under powers given under the new act if they failed to contribute towards fire safety remediation costs.

The act was passed in April, but much of the detail is yet to be finalised, with secondary legislation still to come. It is unclear what impact Greenhalgh’s resignation will have on the future of this process.

In a letter addressed to the PM, Lord Greenhalgh said he had been “saddened at the turn of events” that resulted in Johnson’s resignation and that it had been a “privilege” to serve as a minister in his government.

“Now that the die has been cast, I have decided that this is the right time for me to resign,” he added

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Johnson has said he will remain in Downing Street until the election of his successor and has announced new appointments to his cabinet.

These include the replacement of sacked housing secretary Michael Gove with Greg Clark and housing minister Stuart Andrew, who resigned last week, with Marcus Jones.

The prime minister will also need to replace construction minister Lee Rowley, who also quit in the wake of the scandal over Johnson’s handling over sexual misconduct allegations against former deputy chief whip Chris Pincher.