New Yorkers are urged to wear masks in indoor public settings as scientists work to learn more about the newly identified omicron variant of the coronavirus, the governor and New York City’s health commissioner said Monday.

Gov. Kathy Hochul, a Democrat, said the state won't be “defenseless” if everyone wears masks indoors, gets vaccinated, gets tested, washes their hands and stays home when sick.

"Mark my words, we're going to see a surge in the next five days," Hochul said.

And Dr. Dave Chokshi, the commissioner, said he is “strongly recommending” that all New Yorkers wear masks “at all times when indoors and in a public setting like at your grocery or in a building lobby, offices and retail stores.”

The guidance was in line with the recommendation issued by the federal Centers for Disease Control and Prevention in July that even vaccinated people wear masks indoors in areas where the virus is surging.

Much is still not known about the omicron variant, which was identified last week by researchers in South Africa, including whether it is more contagious than other coronavirus variants, or more able to evade the protection of vaccines.

Cases of the omicron variant have been found in countries including Canada, Australia and the Netherlands, but no cases have yet been detected in the United States.

Mayor Bill de Blasio said that while there have been no cases of the omicron variant reported in New York City, “it is very likely there will be.”

Chokshi, who joined de Blasio at a virtual news briefing, said the delta variant of the virus accounts for 98% of the coronavirus samples from New York City that are being sequenced now.

Hochul said she wasn't ready to announce any new sweeping COVID-19 protocols, like restrictions on visits at nursing homes.

She said she supports recent announcements by Erie County officials, who have warned that the county could start requiring vaccine mandates for indoor dining if rates keep surging.

Vaccination rates are increasing overall in New York, fueled in part by a mandate for health care workers to get vaccinated. New York City has also required vaccinations for city workers and for indoor dining, for example.

But vaccination rates are lower in western New York, the Finger Lakes and other rural communities north of New York City and its surrounding suburbs: as low as 40% in Allegany County, 47% in Wyoming County, and 49% in Yates and Seneca counties.