The head of the World Health Organization on Monday urged countries to carry out the reforms needed to prepare for the next pandemic and honor a previous commitment to boost financing for the U.N. health agency.

Speaking at the WHO's annual health assembly weeks after ending the global emergency status for the COVID-19 pandemic, Tedros Adhanom Ghebreyesus said it was time to advance negotiations on preventing the next one.

"We cannot kick this can down the road," WHO Director-General said in a major address to the agency's member states, warning that the next pandemic was bound to "come knocking."

"If we do not make the changes that must be made, then who will? And if we do not make them now, then when?" he said.

The 10-day annual World Health Assembly in Geneva, which coincides with the body's 75th anniversary, is set to address global health challenges including future pandemics.

The WHO's 194 member states are currently negotiating reforms to the binding rules that fix their obligations in the event of an international health threat and are also drafting a broader pandemic treaty which is up for ratification next year.

"A commitment from this generation (to a pandemic accord) is important, because it is this generation that experienced how awful a small virus could be," said Tedros. Countries are also set to consider later on Monday the WHO's 2024-2025 budget which includes increases to countries' annual fees.