New measures to tackle the rise in coronavirus cases “will take time to feed through”, Prime Minister Boris Johnson has said.
Mr Johnson told a Downing Street briefing that the high number of daily cases and “tragic increase” in deaths “show why our plan is so essential”.
He said he would “not hesitate” to impose further restrictions if needed.
“This is headed in the wrong direction,” said chief scientific adviser Sir Patrick Vallance.
“There’s no cause for complacency here at all,” he said.
It comes as the latest UK coronavirus figures showed there have been a further 7,108 cases and another 71 deaths.
Mr Johnson also said the nation could face the winter “with confidence” because it is now better prepared than it was in March.
The preparations include being on track for 500,000 tests a day by the end of October, 2,000 beds in seven Nightingale hospitals and a four-month supply of protective equipment such as masks, gowns and visors.
He said they had trebled the number of ventilators in the NHS to 31,500 in the last six months.
“I want to thank everyone for the fantastic national effort that we are seeing,” Mr Johnson said.
“No matter how impatient we may be, how fed up we may become, there is only one way of doing this, and that’s by showing a collective forbearance, common sense and willingness to make sacrifices for the safety of others.”
He paid particular tribute to university students, hundreds of whom have been forced to self-isolate, and are “experiencing a first term back at university unlike anything they could have imagined”.
Mr Johnson urged people to use the NHS Test and Trace, saying it had reached 14 million downloads, and said he would resume providing regular Downing Street briefings.
“If we put in the work together now, then we give ourselves the best possible chance of avoiding that outcome and avoiding further measures,” he said.
England’s chief medical officer Prof Chris Whitty told the briefing the number of Covid-19 patients was rising, especially in hotspots, although they remained lower than in early April.
“We are pointing out that the direction of travel for both hospitals and intensive care is going in the wrong direction, particularly in these areas that have seen rapid increases in cases,” he said.
“We have got a long winter ahead of us.”