The UN Security Council on Thursday will try once again to pass a resolution calling for a halt in fighting between Israel and Hamas after previous efforts to win Washington's backing fell short.

Diplomatic wrangling at United Nations headquarters in Manhattan headquarters -- which caused the vote to be postponed again Wednesday -- has come against a backdrop of deteriorating conditions in Gaza and a mounting death toll.

The United Arab Emirates is sponsoring a draft resolution on the conflict which has already been watered down to secure compromise, according to a draft version seen by AFP.

It calls for "the urgent suspension of hostilities to allow safe and unhindered humanitarian access, and for urgent steps towards a sustainable cessation of hostilities."

Countries "are engaging at the highest level of diplomacy to reach a text that will have impact on the ground. Diplomacy takes time," said the UAE's ambassador Lana Zaki Nusseibeh.

"If this fails, then we will continue to keep trying... There is too much suffering on the ground for the council to continue to fail on this."

Members of the 15-member council have been grappling for days to find common ground on the resolution, a vote on which was pushed back several times since Monday.

- 'Final decision' -

Israel, backed by its ally the United States, a veto-wielding permanent Security Council member, has opposed the term "ceasefire," and Washington has used its veto twice to thwart resolutions opposed by Israel since the start of the war.

The latest delay was at the request of the United States, a diplomatic source said.

Israeli Prime Minister Benjamin Netanyahu said Wednesday there would be no ceasefire in Gaza until the "elimination" of Hamas.

"Everyone in New York is still waiting on the White House. There is a strong sense that (US President Joe) Biden will make the final decision on this," said International Crisis Group analyst Richard Gowan.

Washington's UN ambassador Linda Thomas-Greenfield "has pitched hard within the US system for a deal," Gowan said.

"But if the Israelis continue to oppose the resolution, Biden could still decide to block it."

Secretary of State Antony Blinken would not be drawn on Washington's next move at the Security Council, telling reporters Wednesday that the US was engaging "constructively... to try to resolve some of the issues."

He said Washington wanted "to make sure that the resolution, in what it calls for and requires, actually advances (humanitarian) effort and doesn't do anything that could actually hurt the delivery of humanitarian assistance."

The spokesman for UN Secretary-General Antonio Guterres said it is "not for us to interfere with those discussions, which I understand are fairly intense."

"The secretary-general's own position is unchanged -- he's been calling for a humanitarian ceasefire," said the spokesman, Stephane Dujarric.