President Donald Trump has said federal coronavirus guidelines such as social distancing will be extended across the US until at least 30 April.
He had previously suggested that they could be relaxed as early as Easter, which falls in mid-April.
"The highest point of the death rate is likely to hit in two weeks," Mr. Trump said.
He appeared to be referring to peak infection rates that experts fear could overwhelm hospitals.
White House medical adviser Dr. Anthony Fauci had earlier warned that the virus could kill up to 200,000 Americans.
Dr. Fauci said that it was "entirely conceivable" that millions of Americans could eventually be infected.
- Live: Our rolling coronavirus coverage
- Trump backs away from New York 'quarantine'
- What this crisis reveals about the US
The US now has more than 153,000 confirmed cases.
As of Monday afternoon, 2,828 deaths had been recorded in the country in relation to COVID-19, according to figures collated by Johns Hopkins University.
The US last week became the country with the most reported cases, ahead of Italy and China.
What did Trump say?
Speaking during the White House coronavirus briefing on Sunday, Mr. Trump called social distancing measures "the way you win", adding that the US "will be well on our way to recovery" by June.
Suggesting that the "peak" of death rates in the US was likely to hit in two weeks, Mr. Trump said that "nothing would be worse than declaring victory before victory is won - that would be the greatest loss of all".
Analysts suggest that when Mr. Trump referred to a peak in the "death rate", he probably meant the total number of recorded infections.