Hundreds of British citizens being flown back to the UK from Wuhan on Thursday will be put in quarantine for two weeks.
It comes as British Airways suspends all direct flights to and from mainland China because of the coronavirus outbreak.
Australia, Japan, the US and EU nations are also repatriating citizens.
The virus has caused more than 130 deaths, spreading across China and to at least 16 other countries.
The UK government plans to fly 200 British citizens out from Wuhan, the centre of the new coronavirus outbreak, on Thursday.
BBC health editor Hugh Pym said that Health Secretary Matt Hancock has instructed officials to put them in quarantine for two weeks – possibly at a UK military facility.
Sources told the BBC the returning Britons will be given the best possible medical care and advice.
Those returning from other parts of China will not be affected, but have been advised to “self-isolate” for 14 days.
Australia plans to quarantine its 600 returning citizens for two weeks on Christmas Island – some 2,000km (1,200 miles) from the mainland.
British Airways, which operates daily flights to Shanghai and Beijing from Heathrow, announced the suspension of flights to and from mainland China “with immediate effect” until 31 January while it assesses the situation.
A statement said: “We apologise to customers for the inconvenience, but the safety of our customers and crew is always our priority.”
Other airlines, including United Airlines, Air Canada and Cathay Pacific Airways, have already cancelled some flights to China.
What’s happening to people stuck in Wuhan?
Some Britons in Wuhan said they had not been told about the quarantine plan, with one man having refused his place on the flight for fear of spreading the disease.
Kharn Lambert told the BBC’s Victoria Derbyshire programme that the embassy said it is their own responsibility to arrange transport home and isolate themselves.
“I don’t want to put the health of regular, everyday British citizens at risk,” he said.
British lecturer Yvonne Griffiths, who is currently in a hotel in Wuhan, said she was told in the early hours of Wednesday morning that there would be a flight from Wuhan airport to the UK.
“We have to be there six to seven hours before the flight leaves, and we would have a screening from some health people here in Wuhan, and if we are not showing any symptoms then we’ll be able to board that plane,” she said.
“If we were to be suffering temperature or any other symptoms, breathing problems, then there seems to be a possibility of quarantining at this end.”
Another British man, Jeff Siddle, from Northumberland, said that he and his daughter had been offered seats on a flight on Thursday – but not his wife, who’s a Chinese national. China is not allowing its citizens to leave the country.
The number of deaths from the virus has risen to 132 in China, the Chinese National Health Commission (NHC) said on Wednesday.
Four cases have been confirmed in Germany, making it the second European country to report cases, after France.
The United Arab Emirates has also confirmed its first cases of the virus in a family who recently returned to the UAE from Wuhan.
