US federal and state officials in California are preparing to receive thousands of people from the cruise ship that has been idling off the coast of San Francisco for a week.
More than 140 British passengers and crew are on the Grand Princess, which is carrying 21 people who have tested positive for Covid-19.
Passengers were expected to be allowed to disembark the Grand Princess from Monday – a process the liner’s operator said will take a number of days.
A Foreign Office spokesman said: "We continue to work closely with the US authorities to repatriate British nationals on board the Grand Princess.
"The US are currently planning for a flight to leave tomorrow evening, returning to the UK on Wednesday afternoon.
"We remain in contact with all British nationals on board and will continue to offer support."
Britons will be free to go on their arrival in the UK, rather than forced into quarantine.
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Fences have been installed at an 11-acre site at the Port of Oakland as authorities readied flights and buses to take the passengers aboard the ship to military bases or their home countries for a 14-day quarantine.
The more than 3,500 passengers and staff on the ship hail from 54 countries.
The US death toll from the virus has reached at least 21 with the number of infections in the United States climbed above 500 as testing for the virus increased.
US passengers will be transported to military bases in California, Texas and Georgia, where they'll be tested for the COVID-19 virus and quarantined.
A spokeswoman for operator Princess Cruises said: “Disembarkation will commence in order of priority, as defined and directed by both state and local authorities. It is expected to be a multiple-day process.”
The crew will remain on board the ship as it departs from San Francisco Bay once all guests are off, Princess Cruises said.
“Plans for a crew quarantine are still being determined,” the spokeswoman said.