Experts believe the exterior cladding, which contained insulation, helped spread the flames quickly up the outside of the public housing tower early Wednesday morning.
Meanwhile, a company involved in the renovation of the tower was forced to deny cladding on the building was banned in the United Kingdom after comments made by Chancellor Phillip Hammond.
If at least 58 deaths are confirmed, the blaze would be London's deadliest since World War II. He says it will take weeks or longer to recover and identify all the dead at the building.
He says tower residents who survived fear a cover-up will keep the truth from coming out.
A criminal investigation and government inquiry will probe whether the regulations were broken when the building was refurbished, Hammond said.
Cundy said police had now managed to get to the top of the tower and had undertaken a first visual search for victims, ahead of later painstaking searches.
He says it may be necessary for numerous outmoded tower blocks built in the 1970s to be demolished because of safety concerns.
British Prime Minister Theresa May, facing criticism for the government's handling of the disaster, met Saturday with a small group of fire survivors invited to her official residence at 10 Downing Street. This year, however, it is hard to escape a very sombre national mood.
Grenfell Tower fire: Number of people missing feared dead rises above 58
One of them told reporters they spoken to the Prime Minister for two and a half hours about their demands and what they expected. The NSW Master Builders Association said the danger lies in imported products that do not meet safety requirements.
Some 19 patients are still being treated in hospital, of whom 10 are in a critical condition, the National Health Service said. A solemn Elizabeth and her husband Prince Philip held a minute of silence for the fire victims at the start of the procession Saturday.
The local authority and the government have been criticised for their response to the emergency by those who have lost their homes because of the fire and by community leaders, and politicians.
The queen said it was "difficult to escape a very sombre mood" on what is normally a day of celebration.
Scuffles broke out near the Kensington and Chelsea town hall offices Friday as demonstrators chanting "We want justice!" surged toward the doors.
The government has promised a full public inquiry, but that has done little to a sense of frustration at the lack of information about how the fire moved so quickly to engulf the building.
The tragedy has provoked a enormous response from nearby communities that have donated food and shelter to the victim. More than 3 million pounds ($5.1 million) have been raised for the victims.
The tributes could be seen nestled in amongst the growing number of flowers, candles and messages placed near Latymer Community Church on Sunday.
After a turbulent three months which has seen three militant attacks and now the tower blaze, Queen Elizabeth said "it is hard to escape a very sombre national mood", in a message on her official birthday.
Two nearby Underground subway lines were partially shut down Saturday in the fire area to make sure that debris from the tower did not land on the tracks.
However, the spokesman did not confirm what type of cladding was used on Grenfell Tower, adding that this would be subject to investigation. She said, in an unprecedented statement, that she had been "profoundly struck by the immediate inclination of people throughout the country to offer comfort and support to those in desperate need".
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