The number of coronavirus cases in the UK has reached 206 – a rise of 43 since figures were released on Friday.
As of Saturday morning, 21,460 had been tested for the virus, the Department of Health and Social Care said.
It comes as England’s deputy chief medical officer said the UK remained in the outbreak’s “containment” phase.
Jenny Harries told the BBC a decision about the next phase of delaying the spread of the virus would depend on how fast the number of cases rose.
But she said the UK was “teetering on the edge” of sustained transmission.
On Friday, a man in his 80s with underlying health conditions became the second person in the UK to die after testing positive for the virus at Milton Keynes Hospital.
The UK’s first death – a woman in her 70s who also had underlying health conditions – was confirmed on Thursday. A British man also died last month in Japan after contracting the virus on board the Diamond Princess cruise ship.
The UK’s strategy on responding to the virus has three phases – containment, delay, and mitigation – alongside ongoing research.
Up until now, the containment phase has involved catching cases early and tracing all close contacts to halt the spread of the disease for as long as possible,
Moving into the delay phase could see the introduction of “social distancing” measures, such as closing schools and urging people to work from home.
Dr Harries said a decision on formally moving to the next phase would depend on how quickly the number of cases rises.
“We are, if you like, teetering on the edge, but not there just yet,” she said. “We have surveillance systems in place and we’re watching that on a daily basis.”
The delay phase would focus on trying to prevent cases from rising too sharply, pushing the peak of the epidemic out of the winter period and helping health and social care services manage the flow of patients, she said.
Scientific advisers are due to review the evidence next week on measures such as restricting large gatherings, she said.
Dr Harries said they needed to “balance the benefits” with minimising disruption to people’s lives and the economy, as well as ensuring that they are implemented at the time when they will have the most impact.
The updated figures come as US authorities prepare to respond to a coronavirus-hit cruise ship carrying British passengers off the Californian coast, after 21 people on board tested positive for the illness.
US Vice-President Mike Pence said on Friday that the Grand Princess, carrying more than 3,500 people on board, including 140 Britons, had been directed to a non-commercial port for testing.
Jackie Bissell, from Dartford in Kent, said passengers have had little information about what would happen to them since a note was pushed through their door two days earlier saying the virus may be on the ship.
“You can’t go out. You can just go out in the hall if somebody taps your door. They put your food outside, drop your menus inside and that’s about it,” the 70-year-old said.
Dr Harries said she has a “great deal of trust” in the US public health system and said the Foreign Office was “extremely active” in looking after UK citizens abroad.
Globally, the number of coronavirus cases has now passed 100,000, with 3,400 deaths.
The government has updated its advice for travellers from Italy – the country in Europe that has been worst-affected by the virus with more than 4,600 cases.
It now says people who develop symptoms after returning from any part of Italy – not just the north of the country – should self-isolate, while those returning from quarantined areas should self-isolate even without symptoms.
The Foreign Office is also warning travellers to Moscow in Russia that they may be told to self-isolate for 14 days on arrival from the UK, as part of measures to control the virus.
It says in a small number of cases, foreign visitors have been placed in enforced quarantine if they have not complied. (BBC)