WHO's 194 member countries are currently negotiating reforms to the rules that define their responsibilities in the event of an international health threat.
WHO Director-General Dr Tedros Adhanom Ghebreyesus told the annual Health Assembly in Geneva on Tuesday that it was time to move beyond dialogue to prevent the next pandemic.
He warned that nation-states could not afford to ignore it and that the next global pandemic was preparing to 'knock'.
Dr Tedros said: "If we don't make the changes that need to be made, who will?" And if measures are not taken now, when will they be taken?
He added: 'There is a risk of another type of (pandemic) emerging that will cause new increases in disease and death, and there remains the risk of another disease-causing microbe emerging with even more lethal potential. .'
Addressing global health challenges, including future pandemics, is being considered at the 10-day annual World Health Assembly in Geneva to mark the world body's 75th anniversary.
WHO's 194 member countries are currently negotiating reforms to the rules that define their responsibilities in the event of an international health threat.
The assembly is also drafting a comprehensive pandemic agreement that will be submitted for ratification next year.
Dr Tedros said: 'Persistence on the part of the current generation for this agreement is crucial because it is the generation that witnessed how terrifying a small virus can be.'
This warning has come out when a few weeks ago the World Health Organization said regarding Covid-19 that it is no longer a global emergency.
