The body said the United Nations-led initiative to speed up the development of vaccines and medications is facing a huge funding gap.
The project is known as the Access to COVID-19 Tools Accelerator (ACT).
Launched in May, ACT advocates for fair distribution of future vaccines, medications to developing and developed countries.
A WHO spokesperson told Dpa that it has received $2.5billion dollars in pledges.
The UN agency estimates that $31.3billion is needed over an initial period of 12 months.
“We need to prevent vaccine nationalism”, Director General Tedros Ghebreyesus said on Tuesday in Geneva.
He added that the first shipments of vaccines must be available to at-risk people everywhere, not just in a few countries.