World Health Organization chief Tedros Adhanom Ghebreyesus said the prospect of equitable distribution was at "serious risk" just as its COVAX vaccine-sharing scheme aimed to start distributing inoculations next month.
"My challenge to all member states is to ensure that by the time World Health Day arrives on 7 April, Covid-19 vaccines are being administered in every country, as a symbol of hope for overcoming both the pandemic and the inequalities that lie at the root of so many global health challenges", Dr Tedros said.
He said some 39 million vaccine doses had been administered in higher income nations, while just 25 doses had been given in one poor country.
Portugal, which emerged from the first wave of the pandemic with fewer infections and deaths than most European countries, has already almost doubled the overall number of ICU beds since the start of the pandemic, when it had just 528 critical care beds and Europe's lowest ratio per 100 000 inhabitants.
"Ultimately, these actions will only prolong the pandemic, prolong our pain, the restrictions needed to contain it, and human and economic suffering".
A delegate from Burkina Faso, on behalf of the African group, expressed concern at the meeting that a few countries had "hoovered up" most of the supplies.
"Even as they speak the language of equitable access, some countries and companies continue to prioritize bilateral deals, going around Covax, driving up prices and attempting to jump to the front of the queue", he said.
"Not only does this me-first approach leave the world's poorest and most vulnerable people at risk, it's also self defeating".
Apple CEO Tim Cook defends pulling Parler from app store
Amid increasing pressure on Trump for his role in inciting the violence, Parler was banned by Amazon, Apple and Google. Apple, he added, is "always trying to do the right thing".
He urged countries and manufacturers to share doses more fairly around the world.
Covax, the World Health Organization co-led globally-pooled vaccine procurement and distribution effort, has struck agreements with five manufacturers for two billion vaccine doses.
He said that it's not right that younger, healthier adults in rich countries are vaccinated before health workers and older people in poorer countries.
Ninety-two countries - all of them low- or middle-income - will have their vaccines paid for by a fund sponsored by donors.
"Vaccines are the shot in the arm we all need, literally and figuratively", he said.
"We have secured two billion doses from five producers, with options of more than one billion more doses, and we aim to start deliveries in February", Dr Tedros said.
He said the recent emergence of rapidly-spreading SARS-CoV-2 virus variants makes the swift and equitable roll-out of vaccines even more important.
The novel coronavirus has killed more than two million people since the outbreak emerged in China in late 2019.