President Joe Biden will send at least 20 million more Covid-19 vaccine doses abroad by the end of June, marking the first time the United States is sharing vaccines authorised for domestic use.

The move marks a notable pivot from the White House as the administration seeks to use the country's vaccine supply as a diplomatic tool with the pandemic outlook brightening at home.

Biden announced on Monday that his administration will send doses of the Pfizer Inc/BioNTech SE, Moderna Inc and Johnson & Johnson vaccines, on top of 60 million AstraZeneca Plc doses...