President Donald Trump has cancelled the Republican party convention in Florida, citing the pandemic, as US coronavirus cases passed 4 million.
“It’s not the right time for that,” he said, adding that he would still give a convention speech in a different form.
The sheriff in Jacksonville warned this week the city was not ready for such a party jamboree next month.
The event was relocated from Charlotte, North Carolina, after that state imposed social distancing rules.
Although the Jacksonville events have been called off, some delegates will still gather in Charlotte.
Mr Trump told Thursday’s White House coronavirus briefing that safety was his primary concern behind the decision.
At that event, the president will formally accept his party’s nomination to be its standard-bearer in November’s presidential election.
Opinion polls suggest Mr Trump is facing an uphill battle for a second term in office amid criticism of his handling of the pandemic.
Last month, the Democratic convention in Milwaukee, Wisconsin, also due to take place in August, was drastically scaled back.
Mr Trump’s challenger, Joe Biden, will be formally nominated by his party at that event.
In a video released on Thursday, Mr Biden and his former boss, ex-President Barack Obama, poured scorn on Mr Trump.
They highlighted his deflection of blame back in March – “I don’t take responsibility at all” – when asked about delays in Covid-19 testing.
“Can you imagine standing up when you were president, saying, ‘It’s not my responsibility?'” Mr Biden, the former US vice-president, asked in their “socially-distanced” conversation recorded last week.
Mr Obama replied: “Those words didn’t come out of our mouths when we were in office.”
What is the national picture?
The US is recording an average of 2,600 cases per hour, the highest rate globally, according to a tally by Reuters news agency.
On Wednesday, California passed New York – the former epicentre of the US outbreak – for the most confirmed cases with 409,000.
On the same day, Missouri, North Dakota and West Virginia all broke their records for the most new cases in a 24-hour period.
Alabama, Idaho and Texas also reported new record highs in daily deaths.
Across the US on Wednesday, a total 69,707 new virus cases were recorded.