The European Union could authorize a second coronavirus vaccine "in the coming hours", European Council chief Charles Michel said Tuesday, adding that leaders would hold a virtual summit on the health crisis later this month.

National capitals have been pressuring the European Medicines Agency (EMA) to issue its green light for the shot from U.S.-based Moderna as other advanced nations like Britain, the U.S. and Israel press ahead.

The WHO's vaccine advisory group said Tuesday that the second Pfizer-BioNTech anti-Covid-19 vaccine dose could, in exceptional circumstances, be administered a few weeks beyond the recommended 21-28 days.

Members of an international expert team set off for China to investigate the origins of the Covid-19 pandemic, but Beijing has yet to grant them entry, the WHO chief said Tuesday.

"Today, we learned that Chinese officials have not yet finalized the necessary permissions for the team's arrivals in China," Tedros Adhanom Ghebreyesus told reporters.

Schools and colleges across Britain closed on Tuesday ahead of a national lockdown as the country battled to control surging coronavirus cases that are threatening to overwhelm its healthcare system.

German Chancellor Angela Merkel and state leaders are expected Tuesday to extend a shutdown in Europe's top economy as coronavirus deaths continue to mount despite tough restrictions in the run-up to the holidays.

Under mounting pressure to speed up coronavirus vaccinations, Australian Prime Minister Scott Morrison on Tuesday said he would not take "unnecessary risks" and emulate Britain's emergency drug approval.

The sight of French police standing by as 2,500 people broke a national curfew to attend an illegal rave has embarrassed the government and led to questions as to why the partying was allowed to continue for two nights.

Haven, a joint venture of Amazon, Berkshire Hathaway and JPMorgan Chase formed three years ago to make U.S. health care more affordable, announced on Monday it will disband.

Britain on Monday began rolling out the Oxford-AstraZeneca coronavirus vaccine, a possible game-changer in fighting the disease worldwide, while China raced to inoculate millions with a homegrown prophylactic. 

The French government on Monday faced growing pressure to accelerate its Covid-19 vaccination drive, with President Emmanuel Macron reportedly also furious over the slow pace of progress.