Tokyo's foreign ministry says Japan has also requested China to hold discussions over the Fukushima-related import ban based on the provisions of the Regional Comprehensive Economic Partnership trade pact.

Public interest groups, already harshly critical of the original deal for not going far enough, are outraged by the decision.

Under the terms of the new deal, WTO members have six months to decide on whether to extend the measures 'to cover the production and supply of Covid-19 diagnostics and therapeutics'.

The ministerial conference also agreed on deals on e-commerce, responding to pandemics and reforming the organisation itself.

International Trade and Industry Minister Mohamed Azmin Ali says any emergency measures should be targeted and proportionate.

Countries have hit a brick wall trying to secure each separate deal on its own merits, so are now making tit-for-tat offers in an attempt to keep them all afloat.

Under discussion is whether countries that produce more than 10% of global vaccines would be ineligible to use the waiver, or whether countries would self-declare that the waiver should not apply to them.

Top of the agenda at the four-day meeting is the toll Russia's war in Ukraine, traditionally a breadbasket that feeds hundreds of millions of people, is having on food security.

WTO director-general Ngozi Okonjo-Iweala hopes for a final deal by June.

But the global trade body says the compromise would need the backing of all WTO members to come into force.

The US has raised concerns about Russia's actions and will 'use all appropriate means to resolve the matter and keep Russia’s markets open to US exports,' USTR says.

Expectations of new agreements had been muted ahead of the gathering, which was postponed after new Swiss travel restrictions due to the Omicron variant meant many planned face-to-face meetings could not happen.