"Many leaders...have promoted the idea of making any vaccine a global public good, but that should continue to be promoted," WHO director-general Tedros Adhanom Ghebreyesus told a press conference.
"More leaders should join the boat, and we need to have a truly global political commitment and global consensus before we even have the product," he said. "That is what we are pushing."
Tedros was speaking after concerns have been raised that some countries including the United States could hoard any vaccines or drugs they develop to combat COVID-19, with poorer countries not getting access to the treatments they need.
The current situation in Brazil, now one of the global hot-spots for the virus, was of increasing concern especially in cities, the WHO's top emergency expert Mike Ryan said.
Brazil's health system was "still coping," although some intensive care units were at a critical stage and under heavy pressure with more than 90% bed occupancy rates, Ryan said.