Greene King has said it will shut dozens of pubs with the loss of 800 jobs after being hit by tighter restrictions in the face of the pandemic.
The company said it will keep 79 of its sites shut for the time being, with around one third of these closures expected to be permanent.
It called on the Government to provide support for the hospitality sector while tightened restrictions, such as the recent 10pm curfew, remain in place.
A spokeswoman for Greene King said: "The continued tightening of the trading restrictions for pubs, which may last another six months, along with the changes to Government support was always going to make it a challenge to reopen some of our pubs.
"Therefore, we have made the difficult decision not to reopen 79 sites, including the 11 Loch Fyne restaurants we announced last week.
"Around one-third will be closed permanently and we hope to be able to reopen the others in the future.
"We are working hard with our teams to try and find them a role in another of our pubs wherever possible.
"We urgently need the Government to step in and provide tailored support to help the sector get through to the spring and prevent further pub closures and job losses."
The announcement comes after warnings from pub, restaurant and bar bosses that the curfew and other restrictions will result in swathes of job losses across the sector.
Last week, the boss of rival Fuller's said that around a tenth of its almost-5,000 employees could face redundancy without further state support.
The bosses of London-focused groups Young's and City Pub Group also warned that they might have to axe hundreds of roles when furlough ends later this month.