US President Joe Biden walks on the South Lawn to board Marine One at the White House in Washington, DC March 11, 2022. The US government will revoke Russia's most-favored nation trade status amid the Ukraine crisis, the White House said Friday, noting that it will work with Group of Seven (G7) countries and the European Union to roll out new sanctions.Photo:Xinhua

Ireland's prime minister Micheal Martin tested positive for COVID-19 on Wednesday, the country's ambassador to the United States said, forcing him to leave a gala event attended by Joe Biden.

Martin, who holds the position known as the Taoiseach in Ireland, is in Washington and was due to meet President Biden at the White House on Thursday to mark St Patrick's Day.

He was pictured sitting next to House speaker Nancy Pelosi at the Ireland Funds Gala event at the National Building Museum in the US capital shortly before leaving when a PCR test returned positive.

Ireland's ambassador to the US Daniel Mulhall wrote on Twitter: "I filled in for the Taoiseach after he tested positive for COVID-19. I wish the Taoiseach well for his recovery."

Mulhall gave a speech at the event that Martin had been due to deliver.

The Taoiseach was on Thursday scheduled to visit the White House to present Biden with a bowl of shamrock grown in Ballinskelligs, southwest Ireland, in line with a long-established St Patrick's Day tradition. 

Biden said in his speech to the gala event: "I inherited my mother's side of the family's overwhelming pride, overwhelming pride in being Irish."

Martin is feeling well and recovering at the US President's guest property in Washington, Blair House, according to reports. 

It was unclear how his positive result will affect his schedule in the US or his return to Ireland, which will on Sunday hold a national day of remembrance to commemorate those who died during the COVID-19 pandemic.

There have been 79,639,328 infections and 969,780 coronavirus-related deaths reported in the US since the pandemic began. Now COVID-19 infections are decreasing in the country, with 32,823 new infections reported on average each day.