Boris Johnson will bow to international pressure to share part of the UK’s vast vaccine stock with poorer countries, ending months of lockdown.
Details will be announced before the prime minister meets with world leaders – some of whom have donated – at the G7 summit this week, No.10 said.
The move comes after the World Health Organization and other global bodies have pleaded with richer countries to act, to prevent dangerous new variants of Covid from delaying progress on ending the pandemic.
Joe Biden has already announced that the United States will send 25 million doses abroad, three-quarters through the Covax aid program and the rest directly to the countries that need them most.
Emmanuel Macron also said France will send 500,000 shots, some of which are already on their way to West Africa – making two leaders Mr Johnson will meet face to face at the Cornish summit.
In contrast, the UK has only said it will donate certain “excess doses”, with no indication of how many doses will be released or when, as the national immunization program must be completed first.
The UK has gained access to around 400 million jabs – far more than it likely would need – but autumn boosters are now scheduled and children’s vaccinations are increasingly likely.
Downing Street said the UK had “already pledged to share a significant majority of its excess doses” with the Covax program, of which it is the largest donor.
“Later this week, the Prime Minister will announce more details on UK plans to support developing countries by sharing doses the UK does not need,” a statement said.
It is unclear how specific Mr Johnson will be, after a group of 100 MPs and peers urged him to pledge to match every dose bought for the UK with a foreign donation.
The UK claims it has provided global leadership, funding the Oxford-AstraZeneca vaccine and making it available at cost – rather than at a much higher price, with huge profits being made.
Almost one in three vaccines administered worldwide has been the Oxford vaccine – 450 million out of 1.5 billion doses – although some countries prefer the Pfizer-BioNTech version.
Mr Johnson will counter criticism by calling for “concrete commitments” from other G7 leaders to vaccinate “the whole world” by the end of 2022.
“The world expects us to meet the greatest challenge of the post-war period: defeating Covid and leading a global recovery guided by our shared values,” said the Prime Minister.
“Vaccinating the world by the end of next year would be the greatest achievement in the history of medicine.
“I call on my fellow G7 leaders to join us in ending this terrible pandemic and I promise that we will never allow the devastation caused by the coronavirus again. “