The World Health Organisation's (WHO) member countries have approved an agreement to better prevent, prepare for and respond to future pandemics in the wake of the devastation caused by the coronavirus.
Sustained applause echoed in a hall in Geneva, Switzerland, hosting the WHO's annual assembly as the measure - debated and devised over three years - passed without opposition.
The treaty guarantees that countries which share virus samples will receive tests, medicines and vaccines.
Up to 20% of such products would be given to the WHO to ensure poorer countries have some access to them when the next pandemic hits.
WHO director-general Tedros Adhanom Ghebreyesus has touted the agreement as "historic" and a sign of multilateralism at a time when many countries are putting national interests ahead of shared values and co-operation.
Dr Esperance Luvindao, Namibia's health minister and the chairwoman of a committee that paved the way for Tuesday's adoption, said that the Covid-19 pandemic inflicted huge costs "on lives, livelihoods and economies".
"We - as sovereign states - have resolved to join hands, as one world together, so we can protect our children, elders, frontline health workers and all others from the next pandemic," Ms Luvindao added. "It is our duty and responsibility to humanity."
The treaty's effectiveness will face doubts because the United States - which poured billions into speedy work by pharmaceutical companies to develop Covid-19 vaccines -- is sitting out, and because countries face no penalties if they ignore it, a common issue in international law.
The US, traditionally the top donor to the UN health agency, was not part of the final stages of the agreement process after the Trump administration announced a US pullout from the WHO and funding to the agency in January.