The chief medical officer gave the verdict after one month of the lockdown in England and despite a further 1,322 deaths being reported in the past 24 hours.
“Most of my colleagues think we are past the peak. Now, that doesn't mean you can't have another one,” Professor Whitty told the Downing Street press conference.
But – despite the success in vaccinating 10 million people – Boris Johnson said it was soon to give the go-ahead for people to meet up once they have received a second jab.
He ducked a question about when the ‘hotel quarantine’ plan will finally get underway, but said Matt Hancock will reveal more details on Thursday – with the start date thought to be still a fortnight away.
Mr Johnson also faced down pressure from Tory backbenchers for faster school reopening, to match Scotland and Wales, arguing it was “prudent” to stick to 8 March at the earliest.
Professor Whitty, meanwhile, knocked down unofficial hints that every adult could be offered a first dose by the end of May, warning that was “probably beyond what is possible”.
The need to deliver second doses to the oldest and most vulnerable people, after no more than 12 weeks, “will inevitably slow things down” in the months to come.
Both the professor and the prime minister stressed the need for caution, Mr Johnson warning infections were still too “forbiddingly high for us to imagine the relaxation of the current guidelines”.
Professor Whitty said: “There are still a very large number of people in hospital and more people than there were in the first peak in April last year.
He added: "The rates are now coming down but they are still incredibly high.
“If we were to start take-off again from the very high levels we are at the moment the NHS will get back into trouble extraordinarily fast.”
And Professor Whitty dismissed his haranguing by a young man while walking near Westminster, footage of which has being widely shared on social media.
“The odd young lad, showing off, occasionally happens. I didn't think anything of it frankly,” he said.
“I'm sure he'll become a model citizen in due course and hopefully more like Captain Tom, who is the kind of person who I think much more exemplifies the spirit of the UK.
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