The NHS in England will get an extra £3bn of funding to prepare for a possible second wave of coronavirus, Boris Johnson has announced.
The funding will also help ease winter pressures on the health service, Downing Street said.
It follows warnings a second wave this winter could see as many as 120,000 Covid-19 deaths in UK hospitals.
The prime minister made the funding commitment at a No 10 briefing, where he also pledged a new testing target.
Capacity will be increased to at least 500,000 tests a day by the end of October, Mr Johnson said.
Confirming the extra £3bn in funding for the NHS in England, he said Covid-19 could become “more virulent” in winter.
The prime minister said: “Demand for testing is not the only challenge that winter will bring. It’s possible that the virus will be more virulent in the winter months and it’s certain that the NHS will face the usual annual winter pressures.”
He added: “We’re making sure we’re ready for winter and planning for the worst.”
Scotland, Wales and Northern Ireland will also receive additional funds, Mr Johnson added.
Meanwhile, Health Secretary Matt Hancock has called for an urgent review into how coronavirus deaths have been recorded in England.
Downing Street said the new NHS funding would be available immediately and would allow the NHS to continue using additional private hospital capacity and maintain the temporary Nightingale hospitals until the end of March 2021.
This will provide additional capacity for coronavirus patients, as well as allowing the NHS to carry out routine treatments and procedures, No 10 said.
Non-urgent operations were suspended as the UK went into lockdown, to free up hospital beds during the first wave of coronavirus – but in May NHS England told hospitals they should restart procedures.
Highlighting other measures to protect the NHS as it heads into the winter, Mr Johnson said the government would carry out the biggest flu vaccination programme in the history of the health service, while supplies of personal protective equipment (PPE) and ventilators had also increased.