Four more patients in England have tested positive for coronavirus, bringing the total number of cases in the UK to eight.
The four people infected are all known contacts of a businessman who was diagnosed in Brighton last week and who contracted the virus at a conference in Singapore.
Two of the new coronavirus cases involve healthcare workers, Public Health England confirmed on Monday.
A GP surgery in Brighton has temporarily closed after a member of its staff contracted Coronavirus.
The World Health Organisation described the "onward transmission" between UK cases as "concerning", adding: "The detection of this small number of cases could be the spark that becomes a bigger fire."
The news comes as the Government said it was introducing new powers to forcibly quarantine those with the virus.
The PA news agency understands that the decision was in response to one of the Britons who returned from Wuhan attempting to leave isolation.
A Government source said "there was someone who was threatening to abscond from Arrowe Park" - the quarantine facility in Merseyside where Britons repatriated from Wuhan, the epicentre of the virus, are staying.
The movements of the British carrier linked to the other British coronavirus cases:
In a statement England's chief medical officer said: "The new cases are all known contacts of a previously confirmed UK case, and the virus was passed on in France."
The businessman linked to the other cases had attended a conference in Singapore last month. He stopped at a ski resort in the French alps on his way back to the UK, before flying into Gatwick on January 28.
He was checked positive for coronavirus upon his return to Brighton and was transferred to an infectious diseases unit on 6 February.
Tedros Adhanom Ghebreyesus, director general of the World Health Organisation, said the case was one of the "concerning instances of onward transmission from people with no travel history to China.
"The detection of this small number of cases could be the spark that becomes a bigger fire.
He added: "For now, it's only a spark. Our objective remains containment."
Professor Whitty, England's chief medical officer, said the four new cases have been taken to specialist NHS centres at Guy's and St Thomas' and The Royal Free hospitals in London.
In a statement the Royal Free said "there is no risk to any other patients or visitors" at the hospital.
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A further five British nationals, being treated in France, were diagnosed after they came into contact with the same businessman, according to the French health ministry.
The four adults and a nine-year-old child, who are not in a serious condition, were staying in the Alpine resort area of Contamines-Montjoie near Mont Blanc.
The latest confirmed cases come as the Government said it is to introduce new powers to deal with the coronavirus outbreak, which it said is a "serious and imminent threat to public health".
Under the new measures, the Department of Health said people with the virus can now be forcibly quarantined and will not be free to leave.
The powers also allow for people with coronavirus to be forcibly sent into isolation if they pose a threat to public health.
Information on the Department of Health website says Health Secretary Matt Hancock has introduced the new powers in light of the "public health emergency" from coronavirus originating in Wuhan, China.
It comes as the death toll from the disease rose by the most in one day, by 97, reaching 908 early on Monday morning.
All but two of the deaths have taken place in mainland China where the number of confirmed cases has increased to 40,171.
The increases have dented optimism that disease control measures including the isolation of major cities might be effectively battling the outbreak.
Some 3,062 new virus cases were reported over the 24 hours until midnight local time on Sunday, which was a 15 per cent increase from Saturday and broke a string of daily declines.
A spokesman for the Department of Health said the new measures to forcibly isolate cases had been brought in across the UK for people's "own safety.
"We are strengthening our regulations so we can keep individuals in supported isolation for their own safety and if public health professionals consider they may be at risk of spreading the virus to other members of the public."
Dr Nick Phin from Public Health England's National Infection Service said the new confirmed cases "are all closely linked".
As the number of confirmed cases of coronavirus in the UK rose to eight, a statement on the Department of Health website said the virus constitutes a "serious and imminent threat to public health".
The Government said Arrowe Park Hospital on Merseyside and Kents Hill Park in Milton Keynes are now designated "isolation facilities".
Both facilities are housing Britons who have returned from Wuhan on repatriation flights.
In a statement on Monday, Downing Street insisted that the NHS was able to cope with the coronavirus outbreak.
The Prime Minister's official spokesman said: "We are well prepared for UK cases and have robust infection control measures in place to respond immediately, using the tried-and-tested procedures to prevent further spread and the NHS is extremely well-prepared and used to managing infections."