President Joe Biden on Monday said some US hospitals could be "overrun" by Covid cases, but the country is generally well prepared to meet the latest surge and Americans need not panic.

In a virtual meeting hosted by the White House with several state governors and top health advisors, Biden stressed that the rapid spread of the Omicron variant would not have the same impact as the initial outbreak of Covid-19 in 2020 or the Delta surge this year.

"Omicron is a source of concern, but it should not be a source of panic," he said.

Testing is more widely available and mass vaccinations mean that for many people infections do not lead to serious illness.

"Because there have been so many vaccinations and boosters, we're not seeing hospitalizations rising as much as they did previously," he said. "Americans, America have made progress. Things are better."

But "with the rising cases, we still have tens of millions of unvaccinated people and we're seeing hospitalizations rise," he said. There are "hospitals in some places that are going to be overrun both in terms of equipment and staff."

Biden acknowledged that despite surges in testing capacity, it's still not enough.

"Seeing how tough it was for some folks to get a test this weekend shows that we have more work to do," he said.

In addition to expanding free testing sites, the administration is pushing for more home testing kits, Biden said. "There were none when we took office. None. Now we have eight (brands) on the market," he said.

As part of the effort, the government is purchasing 500 million at-home tests for distribution to Americans.

"It's not enough. It's clearly not enough. If we'd known, we would have gone harder, quicker," he said. "We have to do more."

The United States has suffered a pandemic toll higher than any nation on Earth, with more than 816,000 recorded Covid deaths and 52 million cases.