Hospitality chiefs are scrambling to work out whether working lunches at pubs and restaurants could be exempt from new coronavirus restrictions.
Trade body UK Hospitality said it wants government clarification, as many central London venues rely on workers meeting up over lunch.
People from different households are banned from meeting in pubs and restaurants in Tier 2 and Tier 3 areas.
But the rules suggest meetings are allowed for business purposes.
Current government guidance advises working from home as much as possible and limiting social contact.
The question is whether rules allowing necessary business meetings come first, or rules banning the mixing of households, UK Hospitality chief Kate Nicholls told the BBC.
“We don’t know,” she said. “It’s a grey area.”
Businesses will also need to know how they judge whether a lunch is for work purposes or whether potential patrons are breaking the rules, she said.
Last week, UK Hospitality warned that tougher Tier 2 Covid restrictions will put up to 250,000 jobs at risk in London’s hospitality sector.
Households are not allowed to mix indoors, including in pubs and restaurants.
Ms Nicholls said that without additional government support thousands of jobs in the capital will go. “It will be absolutely catastrophic,” she told the BBC.
She has written to the Mayor of London, Sadiq Khan, warning that elevating the capital’s coronavirus risk level “will be incredibly damaging without additional financial support”.
The BBC has approached the government for comment.