Novak Djokovic | AFP
Melbourne: Australia vowed to deport tennis world number one Novak Djokovic on Thursday after he failed to meet stringent pandemic entry requirements, as Omicron's relentless march forced organisers to cancel the Grammys and Sundance Film Festival.
The vaccine-sceptic Serb failed to provide evidence of double vaccination or a medical exemption when he landed to defend his Australian Open crown, prompting authorities to cancel his visa and hold him at the airport overnight.
"Rules are rules and there are no special cases," Prime Minister Scott Morrison said.
Djokovic said he had received a medical exemption to play in the Australian Open before departing for Melbourne, sparking fury among Australians who have endured harsh restrictions since the heavily mutated Omicron variant entered the country.
Tennis' first grand slam of the year is the latest sporting event to struggle with health measures, with next month's Beijing Olympics also impacted by small outbreaks across China that have seen stay-at-home restrictions imposed on millions of people.
Infections in China have reached a high not seen since March 2020 although they remain low by international standards -- with 189 cases reported on Thursday.
In the historic city of Xi'an, where 13 million people have been placed under strict home confinement for two weeks, the restrictions led to tragedy when an eight-month pregnant woman miscarried after a hospital refused her entry without a Covid test.
Videos of the woman sitting on a plastic stool outside the Gaoxin Hospital surrounded by a pool of blood went viral on social media, with Chinese authorities later saying they had punished the officials involved.
Meanwhile, Japan's foreign minister urged his US counterpart to consider restricting American troop movements in the country after a surge in Covid cases on bases and surrounding communities.
The surge took place in Okinawa, which hosts most of the US forces in Japan, with the region's governor blaming the rise on clusters first seen among US troops.
The southern island region reported 981 cases on Thursday -- a record high.
Omicron brought down the curtain on both the Grammy music awards and Sundance Film Festival, with over 2.5 million new infections reported across the United States since Monday.
Citing "uncertainty" surrounding the new coronavirus variant, the Recording Academy indefinitely postponed the music awards, while Sundance organisers said the festival would go virtual.
Omicron accounted for around 95 percent of US cases in the week ending January 1, with new hospitalisations rising.
In Latin America, Brazilian health authorities approved vaccines for children aged five to 11 as case numbers rise.
It followed the cancellation on Tuesday of next month's world-famous carnival street celebrations in Rio de Janeiro.
Europe has also struggled to contain Omicron, the most transmissible Covid-19 variant to date, with official data showing one in 15 people in England were infected with the virus in 2021's final week.
Prime Minister Boris Johnson declared existing travel curbs ineffective against the strain and his government scrapped testing and quarantine measures for travellers.
In Italy, the government said it would make vaccination mandatory for anyone over 50 -- nearly half the population -- to combat surging infections.
France set a record for new cases over a 24-hour period on Wednesday, according to the latest official figures, recording more than 332,000 additional infections -- the first time cases breached 300,000.
The runaway numbers in Europe and North America led Hong Kong on Wednesday to impose a flight ban on eight countries including Australia, Canada, France, Britain and the United States.
The restricted list also included the Philippines, Pakistan, and India, where several cities have imposed curfews and the capital New Delhi has told residents to stay home this weekend.
India recorded more than 90,000 new infections overnight while financial capital Mumbai saw its highest daily count yet in the pandemic.
In the heartland state of Uttar Pradesh, rallies for elections next month were cancelled as confirmed Omicron cases nearly tripled in two days.
"Systems will be overwhelmed, your house will be overwhelmed," V.K. Paul, a doctor working with the government on its coronavirus response, told a press conference on Wednesday.