US President Donald Trump has slammed Nancy Pelosi in a Twitter rant for refusing to reopen the House of Representatives.

In a series of tweets, Trump labelled Speaker of the House Pelosi as ‘crazy’ and said she was using the virus as an excuse not to come to work.

Both Pelosi and Senate leader Mitch McConnell rejected Trump's suggestion that all members could be tested on the basis that frontline staff should take priority.

Trump responded: “No reason to turn it down, except politics. We have plenty of testing. Maybe you need a new Doctor over there. Crazy Nancy will use it as an excuse not to show up to work!”

Pelosi decided against having her members join the Senate in returning next week because the Washington area remains a virus hot spot.

In a joint statement, Pelosi and McConnell said: "Congress is grateful for the Administration's generous offer to deploy rapid COVID-19 testing capabilities to Capitol Hill, but we respectfully decline the offer at this time.

“Our country's testing capacities are continuing to scale up nationwide and Congress wants to keep directing resources to the front-line facilities where they can do the most good the most quickly.”

But Trump continued: “There is tremendous coronavirus testing capacity in Washington for the senators returning to Capitol Hill on Monday. Likewise the House, which should return but isn't because of Crazy Nancy P,” he tweeted.

After Pelosi announced the House would not be reopening on Tuesday, Trump suggested it was because she was enjoying being at home.

“Yeah, I think they are, I think they are [enjoying their vacation]. Look at Nancy Pelosi eating ice cream on late night television, yeah I think they probably are having a good time.”