LONDON — In the wealthy central London enclave of Belgravia, where a two-bedroom apartment is advertised for about $2.4 million, and Maseratis and Bentleys line the streets, the battle for restaurant staff has become downright underhanded.

The manager at Olivo, a Sardinian restaurant, recently kicked out a rival Sardinian restaurateur from the dining room. The man was trying to persuade a waitress to work at his restaurant.

Olivo can’t afford to lose any more staff. Across Britain, there is a dearth of hospitality workers, and companies are getting increasingly desperate to fill vacancies. Until they can, restaurants are partially closing despite huge demand from customers who have saved money during the pandemic and are eager for a great meal out.

Even after months of forced closure, many restaurants would rather forgo revenue than risk their reputation offering substandard service from stretched staff. Recruiters and employers are also trying to work out how to coax reluctant workers into the industry — especially British ones, as Brexit has drained the labor pool of many European workers.

Mauro Sanna, owner of Olivo, recently came to the frustrating decision to close the restaurant for lunch on Saturdays and all day on Sundays because of too few staff, particularly chefs. Another of his restaurants, Olivocarne will be closed on Sunday evenings and all day on Mondays. Olivocarne has four people working in the kitchen but needs seven.

The closures enable the staff to rotate between the restaurants while he tries to fill 15 vacancies, including porters, runners, waiters and a station chef.

“It’s becoming impossible,” Sanna said. “I thought the COVID crisis was tough, but this one is much tougher because I can’t do anything about it. I don’t know what to do.”

Across the hospitality industry, there are approximately 188,000 open positions, according to Kate Nicholls, CEO of UKHospitality, a trade group. Restaurant companies including the Ivy Collection and D&D have hundreds of open positions advertised online. Hawksmoor, a small chain of high-end steak restaurants, is paying staff hefty bonuses for referrals.

Similar problems are hampering the sector in other countries including France and the United States, but in Britain, it has been exacerbated by Brexit.

Before the pandemic one out of four hospitality workers in Britain was from a European Union country, Nicholls said. During 2020, when lockdowns froze much of the economy and huge numbers of workers were furloughed, hundreds of thousands of EU migrants are estimated to have returned home.

When Britain left the European Union single market, the open-door policy that had allowed people from any EU country to work in Britain was shut. Migrants wishing to return to Britain now need to have secured permission from the government. New workers must compete for visas in a points-based immigration system that values highly paid jobs more.

Many workers have taken less strenuous jobs that don’t require late nights and long shifts, such as in call centers or retail. Adecco, a large recruitment agency, sent out a request to tens of thousands of job-seekers to gauge their interest in working in hospitality. Just 1% responded.