U.S. national flags fly at half-mast at the Washington Monument in commemoration of the 19th anniversary of the 9/11 attacks in Washington D.C., the United States, on Sept. 11, 2020. (Photo: Xinhua)

 
U.S. President Joe Biden will order flags at federal properties to fly at half-staff as COVID-19 deaths in the United States close in on the grim milestone of 500,000, White House Press Secretary Jen Psaki said Monday.

"Later today, the President, the first lady, the Vice President and the second gentleman will mark the solemn milestone of 500,000 American lives lost to COVID-19. They will ask all Americans to join in a moment of silence during a candle lighting ceremony at sundown," Psaki said at the White House press briefing.

"President Biden will also deliver remarks and order all flags on federal property to be lowered at half-staff for the next five days," said the press secretary. She said Biden's remarks "will highlight the magnitude of loss that this milestone marks for the American people and so many families across the country."

The COVID-19-related death toll in the United States stood at 499,309 as of Monday noon, according to Johns Hopkins University's tally.