The Michelin-starred the Square restaurant in London's Mayfair has been closed by administrators.
The closure of the restaurant and members club Morton's has been confirmed by administrators after diners were asked to leave during lunch service on Friday.
The Square employs 31 staff while Morton's has 40 employees. It is owned by Marlon Abela, who bought it from Nigel Platts-Martin and Phil Howard in 2016.
The administration follows court action from HMRC to wind up the businesses following non-payment of VAT.
Graham Bushby from administrators RSM said: "At this stage in the process, it is too early to comment on our strategy for the administration.
"We are working closely with management and staff in seeking a positive way forward. We understand that the current situation is uncertain for many staff members across this group of businesses and we will be looking to provide clarity as soon as we can."
In recent years Marc Ltd, the parent company of Marlon Abela's restaurant group has been in uncertain financial health. It fell into liquidation at the end of 2018 and was only rescued by a cash injection from Abela.
In July 2019 the restaurant group, which includes the two-Michelin-starred London restaurants the Greenhouse and Umu, as well as Morton's Club, reported pre-tax losses of £5.76m for the year to 31 December 2017. The accounts showed Abela was owed £47.47m by the company.
The Square was opened by Platts-Martin and Howard in 1991 in St James's. It was awarded its first Michelin star in 1994 before relocating to Mayfair two years later.
A second Michelin star was awarded to the restaurant in 1998, the same year that Howard won the Chef Award at the Cateys. The two stars were deleted in the 2017 Michelin guide following the restaurant's change of ownership. A single star was reinstated in 2018.