LONDON -- Rich countries are on course to have over a billion more doses of COVID-19 vaccines than they need, leaving poorer nations scrambling for leftover supplies as the world seeks to curb the coronavirus pandemic, a report by anti-poverty campaigners found on Friday.

In an analysis of current supply deals for COVID-19 vaccines, the ONE Campaign said wealthy countries, such as the United States and Britain, should share the excess doses to “supercharge” a fully global response to the pandemic.

The advocacy group, which campaigns against poverty and preventable diseases, said a failure to do so would deny billions of people essential protection from the COVID-19-causing virus and likely prolong the pandemic.

The report looked specifically at contracts with the five leading COVID-19 vaccine makers - Pfizer-BioNTech, Moderna, Oxford-AstraZeneca, Johnson & Johnson, and Novavax.

It found that to date, the United States, the European Union, Britain, Australia, Canada and Japan have already secured more than 3 billion doses - over a billion more than the 2.06 billion needed to give their entire populations two doses.

“This huge excess is the embodiment of vaccine nationalism,” said Jenny Ottenhoff, ONE Campaign’s senior director for policy.

“Rich countries understandably hedged their bets on vaccines early in the pandemic but with these bets paying off in spades, a massive course correction is needed if we are going to protect billions of people around the world,” she added.

The analysis found that, along with other COVID vaccine supplies procured by the global COVAX vaccine-sharing plan and in bilateral deals, the excess rich-country doses would go a long way to protecting vulnerable people in poorer countries.

This would significantly reduce the risk of deaths from COVID-19, it said, as well as limiting the chances of new virus variants emerging and accelerating an end to the pandemic.

The World Health Organization on Thursday urged nations with vaccines not to share them unilaterally, but to donate them to the global COVAX scheme to ensure fairness.