A US panel has recommended Johnson & Johnson's one-dose COVID-19 shot for emergency approval, as some of the world's most powerful countries issued a unified call for better vaccine access for poorer nations.
The United States is the world's hardest-hit country, and its emergency use authorization of the J&J vaccine would follow those for the Pfizer and Moderna doses.
"We're going to use every conceivable way to expand manufacturing of the vaccine... and make even more rapid progress," said President Joe Biden as the country tries to finally get on top of the virus that has already claimed 510,000 US lives.
J&J stressed its vaccine was proven to work with a single shot, and could be stored long-term at standard fridge temperatures, which "offers logistical and practical advantages."
Prince William hits vaccine 'infodemic'
Prince William has warned that anti-vaccination messages are rife on social media and urged those eligible to get jabs, following a similar appeal by his grandmother, Queen Elizabeth II.
"Social media is awash sometimes with lots of rumours and misinformation," the Duke of Cambridge said in video footage released by Kensington Palace on Saturday evening.
It showed him and his wife Catherine, the Duchess of Cambridge, speaking to two women who are clinically vulnerable and eligible for first jabs soon.
In one video call, a woman called Shivali, who has type 2 diabetes, said she had read a lot of social media posts that made her "a bit nervous" about getting vaccinated initially, while she was now confident about getting the jab.
The prince told her: "We have to be a little bit careful who we believe and where we get our information from, especially for those who are clinically vulnerable as well, it's so important that these vaccinations are done. Catherine and I are not medical experts by any means but if it's any consolation we can wholeheartedly support having vaccinations, it's really, really important."
Auckland under lockdown anew
Prime Minister Jacinda Ardern ordered New Zealand's largest city back into lockdown as COVID-19 cases continued to be detected in the community.
The latest restrictions in Auckland will last at least seven days and come less than two weeks after a three-day shutdown in the city.
From Sunday morning the city's 1.7 million residents must stay at home except for essential shopping and work. Schools and non-essential shops will close, and entry in and out of the city will be restricted.