He sent a list of requests to the Prime Minister, saying that residents close to where the deadly blaze occurred “feel the government and local council haven't done enough to help”.
This comes as the Guardian has reported that a cheaper cladding was used when the Grenfell Tower was renovated last year, and that the material chosen by sub-contracted firm Harley Facades was less fireproof than the more expensive alternative.
“Residents I spoke to are worried about the risk of this tragic incident happening elsewhere – particularly in tower blocks that have had similar cladding installed as part of renovations,” he wrote.
“People are terrified that the same thing could happen to them.”
Khan added that other factors should be checked as well as cladding, and asked the Prime Minister to provide a list of tower blocks which have been reviewed by the end of the day.
He said that May should set out a timeline for assessments of any remaining blocks.
Survivors of the blaze were also receiving “insufficient support”, Khan wrote, and the authorities needed be more open to sharing information.
“I appreciate that the authorities want to be absolutely certain that any information is correct before it is issued publicly, and the fire brigade, police and coroner are doing a heroic job obtaining this information in extremely difficult circumstances,” he said.
Yet he added that the procedure being followed was more suited to a terrorist attack emergency than a fire.
A number of relief efforts have been established to give some small comfort to the Grenfell residents who lost everything to the flames, including various JustGiving pages which have together raised more than £2m.
But Khan has told the Prime Minister that aid is not necessarily reaching all who need it.
“I heard multiple stories of local residents not being able to access the information they required and being given conflicting advice by the local authority,” he said of his visit yesterday.
“For example, the local authority believe they found housing for all residents affected last night, however there are reports that this was not communicated effectively and some residents are still sleeping in the Westway Sports Centre or with family and friends.”
Khan asked May to confirm that all Grenfell residents would immediately be rehoused in the area.
The mayor also called on May to make speedy progress with the announced public inquiry into the tragedy, requesting that she publish an interim report “this summer at the latest” including all aspects of fire safety standards in high-rise towers.