The World Health Organization (WHO) has agreed on a resolution, the first by any United Nations (UN) agency, calling for immediate access to vital humanitarian aid and an end to the fighting in Gaza.

The resolution – calling for the “immediate, sustained and unimpeded passage of humanitarian relief, including the access of medical personnel” – was adopted by consensus at the end of a special session of the WHO’s Executive Board on Sunday.

It also called on “all parties to fulfill their obligations under international law” and reaffirmed “that all parties to armed conflict must comply fully with the obligations applicable to them under international humanitarian law related to the protection of civilians in armed conflict and medical personnel."

The special meeting of the executive board was only the seventh in the WHO’s 75-year history.

The passage of the resolution “underscores the importance of health as a universal priority, in all circumstances, and the role of healthcare and humanitarianism in building bridges to peace, even in the most difficult of situations,” the WHO said in a statement after the meeting.

The United Nations Security Council (UNSC) has struggled to respond to the deepening crisis in Gaza that erupted after the Palestinian armed group Hamas launched an unprecedented attack on Israel killing 1 200 people and taking more than 200 captive.

In response, Israel declared war on Hamas and has subjected Gaza, which Hamas has controlled since 2006, to relentless attack, killing at least 18 000 people.

The UN says about 80% of the population has been displaced and faces shortages of food, water and medicine along with a growing threat of disease.

On Friday, a resolution for a humanitarian ceasefire put forward by the United Arab Emirates and co-sponsored by 100 other countries failed to pass in the UNSC after the United States vetoed the proposal.

The US is one of five permanent members of the council with a veto.

The vote came after UN Secretary-General Antonio Guterres invoked Article 99 on Wednesday to formally warn the 15-member council of a global threat from the two-month-long war.

WHO Director-General Tedros Adhanom Ghebreyesus said the UN health agency resolution could be a starting point for further action.

“It does not resolve the crisis. But it is a platform on which to build,” he said in his closing remarks to the board.“Without a ceasefire, there is no peace. And without peace, there is no health. I urge all Member States, especially those with the most influence, to work with urgency to bring an end to this conflict as soon as possible."

Fighting resumed this month after a week-long pause in hostilities that allowed some Israeli and foreign captives to be released in exchange for a number of Palestinians held in Israeli jails, as well as for the supply of humanitarian aid into Gaza.

With Israel now stepping up its military actions in the south of the territory of more than 2-million people, calls for an end to the fighting have intensified.

The UN General Assembly (UNGA) is expected to vote as soon as Tuesday on a resolution for an immediate ceasefire, after Egypt and Mauritania invoked Resolution 377 “Uniting for Peace” in the wake of the US veto.

Adopted by the UNGA in 1950, Resolution 377 allows the 193-member body to act where the UNSC has failed to “exercise its primary responsibility for the maintenance of international peace and security”.

Their letter also referred to Guterres’s invoking Article 99 of the UN Charter on December 6.