Coronavirus cases in the UK have risen 46 to 319 over the last 24 hours, according to latest government figures.
The previous day's rise was 67.
Some 280 of the total coronavirus cases are in England, with London having the most at 61.
The figures reflect the situation at 9am on Monday and show that nearly 25,000 people have been tested so far.
Public Health Wales earlier confirmed two of the new cases, which it said they were not linked and that both people had recently been to Italy.
There are now six infected people in the country.
Five of the new cases are in Scotland, taking the total there to 23.
In the capital, Transport for London (TfL) said it was carrying out a "deep clean" of a Southwark office used by a worker who had tested positive.
The organisation did not specify their job, but the building is where it monitors London's roads and controls the Tube network.
The latest figures come as Boris Johnson held an emergency COBRA meeting over the COVID-19 outbreak.
A Downing Street spokesperson said afterwards that the UK was still in the "contain" phase of dealing with the outbreak and was not yet moving to the "delay" stage.
Such a step would require agreement from England's chief medical officer, Chris Whitty, and chief scientific adviser Sir Patrick Vallance.
However, the spokesperson added that the government accepted the virus would spread in a significant way.
Other UK developments:
On Sunday, a man in his 60s died at North Manchester General Hospital, making him the third person to die in the UK after contracting the virus.
He had underlying health conditions and had recently returned from Italy - the country is the worst-affected in Europe with a quarantine order covering 16 million people.
All three people who have died in the UK had pre-existing health conditions.
The first, a woman in 70s, lost her life in hospital in Reading, Berkshire, while the second, an 83-year-old man, died while being treated at Milton Keynes University Hospital.
The Foreign Office has advised against all but essential travel to northern Italy, but said British nationals are still able to leave without restriction.
The Department for Health and Social Care has said those returning from the quarantine areas should self-isolate for 14 days at home - even if they have no symptoms.
Budget airline easyJet is also cancelling some flights to Milan Malpensa, Milan Linate, Venice and Verona airports, with further flight reductions expected.
British Airways said it was "reviewing our schedule" and offering passengers the chance to change their booking.
Meanwhile, the Department for Digital, Culture, Media and Sport will host a meeting with governing bodies and broadcasters on Monday to discuss how to handle the outbreak's potential impact on the sporting calendar.
Culture Secretary Oliver Dowden has said expert teams have been brought together to tackle the potential spread of "misinformation and digital interference" around coronavirus.
And the FCO has said it is "working intensively" with US authorities on arranging a flight for British nationals on the coronavirus-hit Grand Princess cruise ship due to arrive in Oakland, California, on Monday.
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