GENEVA, Switzerland-- A new World Bank financing mechanism will allow developing countries to purchase COVID-19 vaccines collectively through the Covax facility, it was announced Monday.

Covax was set up to ensure 92 developing territories could access coronavirus vaccines to fight the pandemic, with the cost covered by donors.

The new mechanism will allow those countries to buy additional doses on top of the subsidised ones they will already receive via Covax.

Using money from the World Bank and other development banks, the facility says it will make advanced purchases from vaccine manufacturers based on aggregated demand across countries.

The financing mechanism builds on the existing Covax cost-sharing arrangement which aims to provide 430 million additional doses, or enough doses to fully vaccinate 250 million people, for delivery between late 2021 and mid-2022 for the 92 countries.

Those doses could be purchased through new financing arrangement.

Countries should also have some flexibility in selecting to buy particular vaccines that align with their preferences.

Covax is co-led by the World Health Organization (WHO), the Gavi vaccine alliance and the Coalition for Epidemic Preparedness Innovations.

The financing mechanism "will allow Covax to unlock additional doses for low- and middle-income countries" Gavi chief executive Seth Berkley said in a statement.

"As we move beyond initial targets and work to support countries' efforts to protect increasingly large portions of their populations, World Bank financing will help us advance further towards our goal of bringing COVID-19 under control."

- Vaccine inequity -

The WHO has raged against the staggering imbalance in global distribution of COVID-19 vaccine doses.

Nearly 3.9 billion doses of COVID-19 vaccines have been injected around the world in at least 216 territories, according to an AFP count.

In high-income countries, as defined by the World Bank, 95.4 doses have been administered per 100 inhabitants.

That figure stands at just 1.5 doses per 100 people in the 29 lowest-income countries.

Covax has so far delivered more than 138 million vaccine doses to 136 participating territories -- far short of the numbers it hoped.

"Accessing vaccines remains the single greatest challenge that developing countries face," said World Bank president David Malpass.

"This mechanism will enable new supplies and allow countries to speed up the purchase of vaccines. It will also provide transparency about vaccine availability, prices, and delivery schedules." The World Bank said it is making $20 billion in financing available to developing countries to help purchase and distribute vaccines, supporting efforts in 53 countries so far.

According to the Washington-based development lender, many countries have indicated they would like to purchase additional vaccines through Covax, but have the option purchase elsewhere including directly from manufacturers.