Delegates attending the G20 summit in Rome say a two-track pandemic recovery is developing.
Poorer countries with less access to COVID-19 vaccines are bouncing back more slowly than developed nations that accessed vaccines quickly.
The International Monetary Fund's chief, Kristalina Georgieva, said more money needs to be targeted at the problem.
"We believe that we are still $20 billion short to accelerate vaccinations and reach the target of 40 per cent of people, at least, in all countries by the end of this year, 70 per cent by the middle of next year."
French Finance Minister Bruno Le Maire said the increasing divergence between developing and developed countries would be a "major strategic risk for the rest of the world."
Meanwhile, COVID-19 cases continue to rise across Europe.
Ukraine's president on Friday had a very direct message for citizens as he pleaded with people to get jabbed as soon as possible.
"I'm strongly asking you to switch off social networks and switch on your brains," said Volodymyr Zelenskyy.
Croatia has turned dark red on the latest COVID-19 map.
Over the past last 24 hours the country registered 4,392 new coronavirus cases and another 26 deaths. Less than half of the population have been vaccinated and some experts are calling for COVID-19 certificates to be more widely required to encourage more people to get jabbed.
Poland also registered its highest number of confirmed daily cases on Friday in its fourth wave of the virus. Over 9,000 new cases were registered with 102 reported deaths. Health officials urged people to respect the use of masks in public places as an important addition to vaccinations.