However, it is unclear why attendance was lower than initially anticipated. Mr Trump, who spoke for almost two hours on a range of topics, referred to those in the stadium as "warriors", while blaming the media and protesters for keeping supporters away. There were some volatile scenes outside the venue but no serious trouble was reported.

More than 2.2 million cases of Covid-19 and 119,000 associated deaths have been reported in the US, according to data from Johns Hopkins University.

What did Trump say?

In his opening remarks, Mr Trump said there had been "very bad people outside, they were doing bad things", but did not elaborate.

On the coronavirus response, Mr Trump said he had encouraged officials to slow down testing because it led to more cases being discovered. He described testing as a "double-edged sword".

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"Here is the bad part: When you do testing to that extent, you are going to find more people, you will find more cases," he told the cheering crowd. "So I said 'slow the testing down'. They test and they test."

A White House official later said the president was "obviously kidding".

Taking aim at his Democratic presidential rival, Mr Trump described Joe Biden as "a helpless puppet of the radical left".

The president also struck a combative tone when he touched on anti-racism protests - and the toppling of statues - which began after the killing of an unarmed black man, George Floyd, by police in Minneapolis.

"The unhinged left-wing mob is trying to vandalise our history, desecrate our monuments - our beautiful monuments - tear down our statues and punish, cancel and persecute anyone who does not conform to their demands for absolute and total control. We're not conforming," he told the crowd.