COVID-19 masks
People walk through Sky Harbor International Airport in Phoenix where new COVID-19 cases are down but health experts warn cases may rise with the introduction of the omicron strain on December 18, 2021 in Phoenix, Arizona. Image Credit: AFP

Australia's largest state reported a record 2,566 cases on Sunday, including hundreds of cases of the omicron variant. Leadership in New South Wales is under pressure to reintroduce mandatory mask-wearing for indoor settings and QR code check-ins, measures which were relaxed just days earlier.

The Netherlands announced plans to return to a strict lockdown. Meanwhile, omicron cases in the UK tripled in a day, with England "almost certain" to be suffering hundreds of thousands of daily infections of the new variant, experts said. The Mayor of London declared a "major incident" due to the spread, with the UK government reported to be considering a two-week ban on people in England gathering indoors.

President Joe Biden is set to warn the nation of the perils of remaining unvaccinated in a speech Tuesday as omicron takes hold in the US and infections surge. New York state reported 21,908 cases on Saturday, breaking a record for the entire pandemic for a second consecutive day.

Key Developments:

Cases surge in Australia's largest state

Australia's largest state reported a record 2,566 cases Sunday, amid reports that health experts and some members of the government are supporting the reintroduction of mask mandates as the omicron variant spreads.

Testing confirmed that 313 of the cases involved the omicron strain, though state health officials said the majority of infections there are likely to be of that variant. As the numbers surge, the health department said it will only undertake genomic sequencing for the omicron variant in circumstances where it will make a clinical difference to the care of a patient.

New South Wales Premier Dominic Perrottet is under internal government pressure to reintroduce mandatory mask-wearing for indoor settings and QR code check-ins, the Sydney Morning Herald reported late Saturday, citing ministers in his cabinet. Just days earlier, measures were relaxed across the state of more than 8 million people.

Meanwhile, New Zealand reported 55 new COVID-19 cases on Sunday, confirming an additional five cases of omicron cases in recent international arrivals, bringing the total number of new variant cases in managed quarantine to 13. No omicron cases have been active in the community.

Hong Kong will from December 21 ban non-residents traveling from New Zealand, Egypt, Morocco and Qatar after omicron cases were found there, according to a statement late Saturday. Hong Kong residents returning from those places must be fully vaccinated and undergo hotel quarantine for 21 days under the change.

Germany tightens UK travel rules

Germany declared the UK a virus-variant area, its highest-risk designation, and tightened the rules for travelers from Britain to include a mandatory 14-day quarantine after arrival.

The designation takes effect on Monday and stay in force at least until Jan. 3, the Robert Koch Institute, a national infectious-disease agency, said on its website.

New York breaks case record for second day

New York state reported 21,908 cases on Saturday, breaking a record for the entire pandemic for a second consecutive day, Governor Kathy Hochul said in a statement.

Daily infections in New York City, where the surge is shutting down Broadway shows and keeping workers from offices, rose further to 5,263, Mayor Bill de Blasio said on Twitter.

Statewide hospitalizations, which generally aren't increasing as quickly as infections, rose 70 on Saturday to 3,909. Of 290,930 people tested, 7.53% were positive for the virus, a slight decline in a number that has otherwise soared in recent weeks.

Biden to address omicron spread, unvaccinated

President Joe Biden is set to warn the nation of the perils of remaining unvaccinated against the coronavirus in a planned speech Tuesday as the omicron variant takes hold in the US and the nation experiences a surge in cases.

"We are prepared for the rising case levels, and @POTUS will detail how we will respond to this challenge," White House Press Secretary Jen Psaki said.

Biden 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, according to a White House official.

Cyprus tightens rules for UK visitors

Cyprus is tightening rules for travelers from the UK, requiring quarantine while arrival test results are processed, the Associated Press reported, citing the Health Ministry.

The ministry said the new rules were in reaction to the "drastic increase" in infections from the omicron variant in the UK. Passengers who test positive must isolate until health officials give instructions. Also, visitors will be given five rapid tests that they must use during their stay even if their initial PCR test is negative.

Netherlands returns to strict lockdown

The Dutch government announced plans to enforce a stricter lockdown to stem a surge of infections caused by the spread of the omicron variant.

"Omicron spreads even quicker than we feared. That is why we have to act now, to prevent worse," Dutch Prime Minister Mark Rutte said Saturday at a news conference in The Hague. "We are going back into a lockdown."

The tougher measures mean the country pivots from evening restrictions that shuttered shops, bars and restaurants after 5 pm to a so-called full lockdown that allows only supermarkets and essential shops to stay open. They'll take effect on Sunday and last until at least January 14.

S. Africa's omicron center shifts

The center of a fourth wave of coronavirus cases in South Africa that's being fueled by the highly transmissible omicron variant has shifted from the economic hub of Gauteng to the nation's second most populous province.

In the last 24-hours the largest share of new cases were from KwaZulu-Natal at 26%, compared with Gauteng's 21% and Western Cape's 18%, the National Institute for Communicable Diseases said in a statement on Saturday.

Total daily infections stood at 16,080, a 40% decline from Wednesday's record26,976 daily coronavirus cases.

English soccer body makes vaccine plea

The chief executive of the English Premier League has written to its 20 clubs, urging them to "strongly encourage" players to get vaccinated.

"It has never been more important," Richard Masters said in the letter. His comments come as six of the weekend's top-flight matches were postponed because of COVID outbreaks at some of the clubs.

According to the BBC, 25% of players in the second-tier English Football League say they don't intend to get inoculated.