Former US. Vice President Joe Biden speaks during a rally in Philadelphia May 18, 2019. (Xinhua/Liu Jie)

Joe Biden, the presumptive Democratic presidential nominee, emerged from more than two months of seclusion Monday, wearing a black face mask during a visit to lay a wreath on the day the US honors its war dead.

Biden's last public appearance was March 15 when he faced off against his former Democratic rival Bernie Sanders for a debate in a television studio held with no live audience.

"It feels good to be out of my house," said the 77-year-old, who has remained in isolation at his home in Wilmington, Delaware in keeping with recommended measures to protect the elderly and prevent the spread of COVID-19.

According to the candidate, he and his wife have left their home only for occasional walks or bike rides since mid-March.

"Thank you for your service," the former vice president said to a well-wisher after paying his respects at the Veterans Memorial Park in New Castle, Delaware.

Biden wore a mask covering his mouth and nose for the brief ceremony, in contrast with his rival for the US presidency, Donald Trump, who has yet to wear a mask in public.

Biden and his wife Jill placed a wreath of white flowers at the Delaware memorial park and observed a moment of silence during the brief ceremony before returning to their motorcade.

Asked by a reporter if he had a message for the country, Biden's reply was difficult to hear.

Trump and his wife Melania took part in a wreath-laying at Arlington National Cemetery, before traveling to Fort McHenry in Baltimore where the president delivered a speech in honor of America's war dead - and paid tribute to the military men and women who "raced into danger" in battling the coronavirus pandemic.

COVID-19 restrictions created big obstacles for Biden's campaign, at a time when Trump enjoyed high visibility through near-daily White House pandemic briefings.

Biden abruptly cancelled a rally in Ohio on March 10, replacing it with a speech to a half empty hall in Philadelphia that evening, followed by a news conference at a Wilmington hotel on March 12.

Although he has celebrated primary victories while in confinement, he has been forced to conduct his campaign online for more than two months from a television studio installed in his basement.

Biden previously apologized Friday for telling a black radio host that African-Americans "ain't black" if they are unsure who to support in November's election, sparking accusations of racism.

He made the remark during a spirited and sometimes contentious interview with popular syndicated radio personality Charlamagne Tha God.

"I shouldn't have been such a wise guy. I shouldn't have been so cavalier," Biden later said on a call with black business leaders, after the remarks sparked uproar.

AFP