Former US Vice President Joe Biden said Monday that time had been wasted in the US response against the coronavirus outbreak.

Addressing a virtual event, Biden said the scale of the loss from the public health crisis, which has infected more than 1.5 million people and killed over 90,000 in the United States as of 4:03 p.m. (2003 GMT), is "staggering" and "infuriating."

"But more than that, it's heartbreaking to think how much fear, how much loss, how much agony could have been avoided if the president hadn't wasted so much time and taken responsibility," he said.

"We got denials, delays, distraction -- many of which were openly xenophobic," he added.

Biden, the presumptive 2020 Democratic presidential nominee, along with other Democrats, has ramped up criticism of US President Donald Trump, whom the former vice president will challenge in this year's election, over the handling of the coronavirus pandemic.

Barack Obama, Trump's predecessor, also took a shot.

"More than anything, this pandemic has fully, finally torn back the curtain on the idea that so many of the folks in charge know what they're doing," Obama said during a virtual commencement speech on Saturday. "A lot of them aren't even pretending to be in charge."

Trump fired back at Obama and Biden on Sunday, claiming that the Obama administration "is turning out to be one of the most corrupt and incompetent in US history."