Countries on Friday approved a hard-fought resolution urging WHO action on towering health needs in war-ravaged Gaza, after Israel secured an amendment requiring the text to also mention hostages held in the Palestinian territory.

World Health Organization member states overwhelmingly voted for a text calling for a donor conference towards health needs in the Palestinian territories, and for more reporting on the "catastrophic" situation in Gaza and on Israel's "wanton destruction of health facilities".

But the vote went through only after Israel managed to ensure the text was expanded to include a call for the release of the hostages held in Gaza and a condemnation of the militarisation of hospitals in the territory by Hamas.

Any decision "that does not demand the immediate and unconditional release of all hostages is an unforgivable moral failure", Israel's ambassador, Meirav Eilon Shahar, said Wednesday at the World Health Assembly, the annual gathering in Geneva of the WHO's 194 member states.

After days of diplomatic wrangling and mutual accusations of politicisation of what was meant to be a technical text, the amended resolution was approved by a key assembly committee with 102 votes in favour.

Only six countries, including Israel and its top ally the United States, opposed the resolution, while 69 countries with voting rights abstained or were absent.

"It's a matter of some regret that this operational decision which addresses the appalling health conditions on the ground has become the object of a politicised debate," Noel White, Ireland's ambassador to the UN in Geneva, told the assembly, echoing a sentiment expressed by many.

The original text, presented Wednesday by a group of Arab countries, including the Palestinians, had been expected to pass easily, as similar resolutions have done annually for more than 50 years.

But before the text could go to a vote, Israel surprisingly secured enough support for its amendment, spurring the Arab Group to attempt, in vain, to retract the entire resolution.

Instead of opting to vote against their own resolution, the Arab states decided to push through three amendments of their own, beefing up criticism of Israel, including slamming its "indiscriminate attacks" on health facilities.

"We regret that the three amendments adopted today have made an unbalanced text even more problematic," US ambassador Sheba Crocker told the assembly.

The Gaza war was sparked by Hamas's October 7 attack on southern Israel, which resulted in the deaths of 1,189 people, mostly civilians, according to an AFP tally based on Israeli official figures.

Militants also took 252 hostages, 121 of whom remain in Gaza, including 37 the army says are dead.

Israel's retaliatory offensive has killed at least 36,224 people in Gaza, mostly civilians, according to the Hamas-run territory's health ministry.