- Joe Biden is to address the nation Tuesday as COVID-19 cases rise amid the Omicron variant.
- He will issue a "stark warning" to unvaccinated people, Press Secretary Jen Psaki said.
- He will set out "what the winter will look like" for those who "choose to remain unvaccinated," she added.
Joe Biden is to address the nation Tuesday to outline extra steps he will take to deal with the Omicron coronavirus variant and deliver a "stark warning" to people who remained unvaccinated.
White House Press Secretary Jen Psaki on Saturday tweeted the president "will announce new steps the Administration is taking to help communities in need of assistance, while also issuing a stark warning of what the winter will look like for Americans that choose to remain unvaccinated."
She added: "We are prepared for the rising case levels, and [the president] will detail how we will respond to this challenge.
"He will remind Americans that they can protect themselves from severe illness from COVID-19 by getting vaccinated and getting their booster shot when they are eligible."
The words signal a shift in messaging from the White House. As of December 16, more than 240 million Americans had had at least one dose of a vaccine — around 73% of the total population.
The seven-day average of daily cases was at 127,692 at December 18, up from 85,139 on December 1. The Omicron variant is a growing proportion of US cases, after it drove case surges in other countries.
Early data suggests Omicron may be more transmissible but cause less severe illness than other coronavirus strains, Insider's Aria Bendix reported.
The Centers for Disease Control and Prevention predicts that COVID-19 cases and deaths will increase in the US over the next month, with its latest model projecting more than 40,000 further deaths by January 8.
New York reported on Friday 21,027 new COVID-19 cases in a single day, the highest the state has ever recorded.
Biden outlined extra measures earlier in December to combat the rise in cases, including boosters for all adults and expanded at-home testing.
The announcement he will address the nation Tuesday follows Vice President Kamala Harris saying the administration "didn't see" the Delta or Omicron variants coming.
She told the Los Angeles Times: "We didn't see Delta coming. I think most scientists did not — upon whose advice and direction we have relied — didn't see Delta coming.
"We didn't see Omicron coming. And that's the nature of what this, this awful virus has been, which as it turns out, has mutations and variants."