Cladding samples from 27 high-rise buildings in 15 local authorities have failed safety tests in the wake of the Grenfell Tower disaster, the Government has said.
The Department for Communities and Local Government's announcement comes amid a national safety operation to identify buildings with cladding like that used on the tower block in north Kensington.
Portsmouth and Brent were named along with Camden, Manchester, Plymouth and Hounslow as local authorities with buildings that failed tests.
In Sheffield, problem cladding has been identified in Harold Lambert Court, in Hyde Park.
The cladding is being checked by management firm Together Housing, with cladding samples sent for analysis.
Four tower blocks housing up to 4,000 people on Camden's Chalcots Estate have been evacuated over fire safety concerns.