The European Union has contributed an additional 500 million euros ($606.3 million) to the World Health Organization-backed COVAX programme to supply COVID-19 shots to emerging economies, doubling the bloc's contribution, the European Commission said on Friday.

The contribution consists of a 300 million euro grant and 200 million euros in guarantees by the European Fund for Sustainable Development plus (EFSD+) that will back a loan by the European Investment Bank, the commission said.

UN health agency WHO, along with the GAVI Vaccine Alliance and the Coalition for Epidemic Preparedness Innovations, are spearheading COVAX to secure and distribute vaccines to poorer countries and to ensure shots do not go only to wealthy nations.

They are targeting to deliver 1.3 billion doses of COVID-19 vaccines to 92 low- and middle-income countries by the end of 2021, and the WHO has endorsed vaccines made by Pfizer and AstraZeneca.

"With this new financial boost we want to make sure vaccines are soon delivered to low- and middle-income countries. Because we will only be safe if the whole world is safe," European Commission President Ursula von der Leyen said at the G7 virtual meeting.