The aim of the document, alongside a series of updates to existing rules on dealing with pandemics, is to shore up the world’s defences against new pathogens after the COVID-19 pandemic killed millions of people.

Talks to draw up a global pact to help fight future pandemics are likely to miss an initial deadline on Friday, three sources close to the process said.

Negotiators from the World Health Organization’s 194 member states were hoping to have a final draft agreement by the end of Friday, with a view toward adopting the legally-binding text at the World Health Assembly later this month.

Instead talks on the text may have to continue, sources said, as countries grapple with key sticking points.

"There is no chance at all of us reaching agreement by Friday," said one Western diplomat.

The aim of the document, alongside a series of updates to existing rules on dealing with pandemics, is to shore up the world’s defences against new pathogens after the COVID-19 pandemic killed millions of people.

But there have been deep disagreements throughout the negotiating process, particularly around equity. The accord, commonly known as a treaty, has also become politicised in some countries.

"Talks will continue to Friday night, 00.00 hours,” Roland Driece, one of the co-chairs of the intergovernmental negotiating body leading the treaty talks, said in an email. "Then, we will discuss where we stand and what needs to be done."

WHO chief Tedros Adhanom Ghebreyesus said this week teams were “strongly committed to finalizing the agreement in time for the World Health Assembly.”

Some of the treaty’s most contentious elements, including details around a “pathogen access and benefits system”, have already been pushed back for later discussion, with a deadline two years from now. The system intends to codify sharing of material with pandemic potential, such as new viruses or strains, and ensure that all countries benefit fairly from vaccines, drugs and tests developed as a result.

The existing draft treaty includes a clause asking pharmaceutical manufacturers to reserve 10% of such items to donate to the WHO, and 10% for the agency to buy at affordable prices, to distribute in poorer countries during health emergencies.