Residents remaining in four tower blocks evacuated over fire safety concerns in the wake of the Grenfell Tower disaster will be told they "must leave", Camden Council has said.
The ongoing effort to clear the Chalcots Estate in north London comes after the Government revealed all of the 34 high-rises that have so far submitted cladding samples have failed combustibility tests.
The buildings are located in 17 local authorities across the country, including Manchester, Plymouth, Portsmouth, and Camden, Barnet, Brent, and Hounslow, in London.
Communities Secretary Sajid Javid urged local authorities and housing associations to continue to submit samples "as a matter of urgency" amid a nationwide safety operation launched after at least 79 people died when fire ripped through Grenfell Tower in north Kensington on June 14.
Some 3,000 Chalcots residents face weeks in temporary accommodation after Camden Council leader Georgia Gould said the authority took the "extraordinary action" to clear 600 flats because "we are really clear that those four blocks are not safe".
London Fire Brigade inspecting officers identified concerns over the combination of external cladding, fire doors, gas pipes and insulation, she added.
But despite being urged to leave by officials, around 20 households had refused to vacate their homes, in Taplow, Burnham, Bray and Dorney blocks, by Saturday evening.
On Sunday, Ms Gould said: "This morning council staff will conduct further door knocking to ask those who remain to leave, and issue another letter reiterating to residents who are still remaining in the Taplow, Bray, Dorney and Burnham blocks, that they must leave.
"By remaining in the blocks these residents risk delaying the work that is required and that we are undertaking to make these homes safe.
"It is not safe to remain in these blocks and our residents' safety will continue to be the council's number one priority."
Nearly 200 offers of accommodation have been made to the displaced residents, most of which have been accepted, she added.
Ms Gould committed £100,000 of council funds to pay for food and essential items residents may need, with the council having already spent £500,000 on hotel rooms for residents.
The council said it could take two to four weeks for the four blocks to be made safe.
Refurbishment of the Chalcots Estate was overseen by Rydon, the company involved in the refit of Grenfell Tower, according to the Rydon website.
The site said the Chalcots project was a £66 million refurbishment which lasted 191 weeks.
The work included external thermal rain screen cladding on five towers, new aluminium thermally broken windows on five towers, and an overhaul of external roofs.
It added that 711 flats were modernised with new wiring, heating, kitchens and bathrooms.
Meanwhile, the latest patient figures for the Grenfell Tower fire show that five people remain in three London hospitals, two of whom are in critical care.
About 50 residents displaced from their homes in the Chalcots Estate stayed in nearby Swiss Cottage Leisure Centre on Saturday night, a Camden Council spokesman said.
London Mayor Sadiq Khan has backed the council's decision to evacuate the tower blocks.
"I think they've done the right thing. Look, you've got to err on the side of caution. You can't play Russian roulette with people's safety," he told Sky News On Sunday.
"They've received the advice from the experts and they've acted on the advice, and I'm hoping, because the council speedily asked for mutual aid from other councils across London, because the Government has said they're committed to helping councils who need their help, we'll see, as soon as possible, the remedial repairs, the repair work being done on the buildings to make it safe, so families can go back to their homes.
He recognised it was "terribly inconvenient" and "a huge nuisance" for families to be moved from their homes.
He added: "But the council's done the right thing because what can't be acceptable is, when a council knows a building's unsafe, for the council to still allow people to occupy those buildings."
Ms Gould was back out in the community speaking to those affected on Sunday, as she attended an Eid celebration held at Swiss Cottage community centre.
Three days after evacuation orders were executed, she told those gathered at the event where free food had been supplied by local restaurants, that she knows it has been an "incredibly difficult few nights" and apologised for the "stress and disruption".
She reassured those affected they will be working "24/7 to get the buildings ready", and thanked everyone for their "patience and resilience".