US President Joe Biden will announce plans on Thursday to buy and donate 500 million doses of the Pfizer coronavirus vaccine to more than 90 countries, while calling on the world's democracies to do their part to help end the deadly pandemic, the White House said.

Biden will announce the vaccine donation - the largest ever by a single country - ahead of his meeting with leaders of the other Group of Seven advanced economies - Britain, Canada, France, Germany, Italy and Japan - in Cornwall, England.

The Democratic president arrived in England late Wednesday for his first overseas trip since taking office. The eight-day mission aims to rebuild trans-Atlantic ties and reframe relations with Russia after four rocky years of tariffs and withdrawal...