Bosses at restaurant chains including Itsu, Pret A Manger and Wagamama's have urged the Prime Minister to increase support for the UK's dining sector to prevent mass redundancies.
A letter to Boris Johnson signed by 90 restaurants also calls for major tax breaks and financial support until the social distancing rules have ended, and comes as pressure grows on the Government to reduce the distancing from two metres to one.
They wrote: "Without Government support to help restaurants to generate revenue and cover costs, tens of thousands of restaurants may be forced to permanently close their doors in the coming months."
Welcoming the steps, including the Government's Coronavirus Job Retention Scheme and cheap taxpayer-backed loans to businesses, the owners warned job losses can be expected. The letter said: "This crisis is far from over and the potential consequences are deeply concerning. A huge number of restaurants across the country are facing the prospect of bankruptcy."
A recent survey by Deliveroo, which organised and signed the letter, found more than half of small and independent restaurants said they would have to close within three months without further support.
"Without Government support to help restaurants to generate revenue and cover costs, tens of thousands of restaurants may be forced to permanently close their doors in the coming months," it continued.
The letter suggested that as long as social distancing measures remain in place restaurants should be given grants for updating sites to become Covid-secure, cut VAT, reduce tax burdens, extend the furlough scheme and offer landlords mortgage holidays.