Boris Johnson is to chair a meeting of the government’s emergency Cobra committee later, after the number of UK coronavirus cases jumped to 36.
Senior ministers and health advisers will be told that the virus will present a “significant challenge”.
But the prime minister will say the government and NHS are well-prepared and will “stop at nothing” to fight it.
The official government plan on how to tackle the spread of the virus will be finalised and signed off at the talks.
More UK cases are expected to be announced, after 13 new patients were diagnosed on Sunday.
The latest cases included 12 more in England and the first patient in Scotland, meaning the virus has now reached all four parts of the UK.
Three of the new cases in England were linked to a man from Surrey, who was the first patient to not have been abroad recently and was instead infected within the UK.
Meanwhile, more British holidaymakers stuck in a quarantined hotel in Tenerife are preparing to return home once they test negative for the virus.
Around 150 Britons are now in their seventh day at the H10 Costa Adeje Palace after a group of Italians contracted the virus – and are awaiting test results before they can arrange flights.
Last week concerns about the outbreak wiped more than $5tn from global stocks. But prices in Asia began to rise on Monday after Japan’s central bank promised to take action to support the markets.
The government has said its plan if the outbreak worsens could include asking newly-retired doctors and nurses to return to the NHS.
People could also be urged to work from home – and closing schools and cancelling major public events have also not been ruled out.
“There now seems little doubt that it will present a significant challenge for our country,” Mr Johnson is expected to tell the meeting, which will involve the UK’s chief medical adviser as well as Scottish First Minister Nicola Sturgeon.
“This battle plan lays out in detail the measures we could use – if and when they are needed.”
The government has also set up a “war room” in the Cabinet Office to roll out a public health campaign encouraging people to wash their hands for 20 seconds or more.
Where are the latest cases?
On Saturday, three new cases were confirmed in Gloucestershire, Hertfordshire and Berkshire.
Then, on Sunday, 13 new cases were revealed:
- Three of them were close contacts of the man from Surrey, who was announced as testing positive on Friday. They included another person from Surrey and two people from West Sussex who were all “part of an adult family cluster”, Public Health England said.
- Another new case from Essex had “no relevant travel” and it was unclear how they had contracted the virus.
- The remaining eight had visited affected areas – six to Italy, and two to Iran. They were from London, West Yorkshire, Greater Manchester, Hertfordshire and Gloucestershire, and included:
- Scotland recorded its first case – a patient from the Tayside area who had recently travelled from Itay.
On Sunday, Health Secretary Matt Hancock said the UK was still in the “containment” phase of the outbreak – one of four phases:
- Containment – caring for any infected people and identifying their close contacts
- Delay – deciding what actions to take to slow down the spread
- Mitigation – damage limitation if the virus spreads widely
- Research – constant and ongoing work to inform the three other phases
He said no tactics will be “off the table” and the battle plan drawn up for the worst case scenario – which will be discussed at the Cobra meeting – includes banning big events, closing schools and dissuading people from using public transport.
BBC health editor Hugh Pym said the strategy seems to be to warn that difficult measures may be needed while focusing on trying to contain the spread of the virus.
Labour has said there are growing concerns about the PM’s handling of the outbreak and “serious questions about capacity in our overstretched NHS”.
The party’s health spokesman, Jonathan Ashworth, said the health secretary should update MPs on the government’s response and plan “so that we can properly scrutinise it”.
Meanwhile, Lib Dem MP Layla Moran has written to the health secretary to urge him to make sure people are paid if they have to self-isolate.
The GMB union has also called on NHS trusts to ensure that outsourced staff are given sick pay in suspected cases of Covid-19.
It warned most private companies providing the NHS with cleaners, porters and caterers do not offer sick pay for the first three days.
What do I need to know about the coronavirus?
- WHAT ARE THE SYMPTOMS? A simple guide
- WAYS TO PREVENT CATCHING IT: How to wash your hands
- WHERE ARE WE WITH A VACCINE? Progress so far
- A VISUAL GUIDE TO THE OUTBREAK: Virus maps and charts
- WHAT DOES IT MEAN FOR MY HOLIDAY? Your rights as a traveller
As of 09:00 GMT on Sunday, the Department of Health said a total of 11,750 people had been tested in the UK.
Globally, around 86,000 people have been infected, with cases in more than 50 countries. About 3,000 people have died – the vast majority in China’s Hubei province, where the outbreak originated in December.
In other developments:
- The Foreign Office has announced some British Embassy staff are being withdrawn from Iran because of the outbreak in the country. Iran reported 385 new cases on Sunday, bringing the total to 978 so far. The death toll rose to 54
- Foreign Secretary Dominic Raab has tested negative for the virus. The Foreign Office said he self-isolated after feeling unwell this week – and has now returned to work
- France has banned all indoor gatherings of more than 5,000 people and in Paris the Louvre museum did not open on Sunday.
- Australia and Thailand recorded their first fatalities from the virus on Sunday.
- The leader of a religious sect in South Korea – which is facing the worst outbreak outside China – could face a homicide investigation over some of the country’s deaths, after being accused of hiding the names of some members as officials tried to track patients before the virus spread
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