The coronavirus outbreak in the UK should plateau after rising for the next two to three weeks, the medical director at Public Health England has said.
However Paul Cosford has warned there be an increase in the numbers of those infected over the next fortnight.
Tuesday was the deadliest day for the pandemic in the UK with 563 people reported to have died in the 24 hours before 9am on Wednesday.
The latest figures on cases and deaths countrywide are expected later today.
When asked about the 31% rise in the latest UK death toll numbers, Prof Cosford said the day-to-day numbers were difficult to
interpret on one day's change.
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"My expectation ... is that we will continue to see an increase in the numbers of people being infected and admitted to hospital over the next two to three weeks but we should hit a plateau if all the social distancing measures are working in about two to three week's time, maybe longer."
However that does not mean the social distancing measures will be relaxed soon.
He warned Brits to hunker down for the long haul.
Prof Cosford told BBC Breakfast: "Our expectation is to see ongoing increases [in cases] for two to three weeks yet."
The medical chief said if cases plateau and then come down, lockdown measures could be “reviewed and in due course perhaps lightened a little - but we’re nowhere near being able to say that.”
Prof Cosford refused to rule out daily deaths hitting 1,000 by this weekend.
He told BBC Radio 4’s Today programme: “The day to day numbers are difficult to interpret on one day’s change.
“Obviously there was a big increase yesterday, there had been some reductions in numbers over the weekend and the early part of the week. So what we’re really looking at is the trend."
The comments came as the government faced fury over the slow pace of testing for Covid-19, which lags far behind countries like Germany.
Prof Cosford said: "Our role has always been to - and I speak from Public Health England (PHE) - make sure our labs are doing what they need to do and we're rolling tests out to the NHS for clinical treatment of patients.
"There is some capacity that is available within that in order to start testing NHS staff and that's being done.
"You've heard about the 2,000 yesterday - nowhere near where we need to get to but it's a good start - and then there's the drive-through systems that are beginning."
Asked why other testing facilities were not being used, Prof Cosford said PHE is most closely involved in NHS testing before adding: "The second (strand) is how we can use all of those laboratories, all of that capacity, to boost up at least 100,000 tests a day, hopefully more."
Prof Cosford said he would expect this work to be in place "over the coming days and a small number of weeks".
