A deadly Saudi-led coalition airstrike that hit a wedding in Yemen on Monday predominantly killed women and children, according to UN officials who spoke with VICE News.

Upwards of 130 people reportedly died when the airstrike struck tents full of people in Al-Wahijah, a village near the port of Mokha in the western part of the country. According to some reports, the wedding was for someone associated with the Houthis.

"We can confirm the airstrike struck a wedding party," Ravina Shamdasani, a spokeswoman for the UN's human rights office, told VICE News. "In Yemen, they separate women and men at parties — the airstrike hit the womens' party, and that's why the majority of victims are women and children."

The coalition denied that an airstrike had taken place in the vicinity of al-Wahijah.

The first accounts of the airstrike emerged as UN Secretary-General Ban Ki-moon told world leaders that the Saudi-led bombing campaign had killed a disproportionate number of Yemen's civilians since it began in late March.

"All sides are showing disregard for human life — but most of the casualties are being caused by airstrikes," Ban told world leaders as he opened this year's general debate. "I call for an end to the bombings, which are also destroying Yemeni cities, infrastructure, and heritage."

UN officials said Ban's language, and an explicit call for an end to air operations targeting Houthi rebels and their allies, expressed a growing frustration with the Saudi coalition, which operates with the blessing of Yemen's president, Abd Rabbuh Mansur Hadi.

Hours later, the Secretary-General's office further condemned the airstrike, saying it may have killed "as many as 135 people."

The UN's outspoken denunciation of what may be the conflict's deadliest single attack also coincided with what appeared to be a shift in position on the part of American officials, who told VICE News on Tuesday that they supported initiatives to establish a human rights mission to investigate crimes committed in Yemen. The US, which provides logistical and targeting support to the coalition — in addition to selling billions of dollars in armaments to Gulf States — wavered for more than a week after the Netherlands introduced a resolution authorizing such a mission at the UN's Human Rights Council in Geneva.

On Tuesday, however, a spokesperson for the US mission in Geneva, told VICE News, "Yes, we support the Dutch position." But the Dutch resolution could still change, and the spokesperson refrained directly from calling for an international investigation.

Complicating matters in recent days was a dueling text, introduced by Gulf States, including Saudi Arabia, shortly after the Dutch resolution. The alternative resolution did not reference a UN human rights investigation, but gave preference to an existing national inquiry established by the Yemeni government on September 7.

This week, the Netherlands and the Saudis, along with Yemen, tabled new versions of their resolutions. In their first proposal, the Dutch had already toned down certain language, stopping short of calling for a Commission of Inquiry, as was established for Syria. The latest text still requested the UN's human rights office, "together with relevant experts and dedicated support staff, to monitor the situation of human rights to collect and conserve information."

The team, according to the Dutch resolution, would have access to the entire country and "all relevant parties" in order to "establish the facts and circumstances of serious violations and abuses committed by all parties in Yemen since September 2014."

The Saudi counter-proposal, which human rights groups already called laughable, was further watered down in its new form. Not only does it not call for an international, independent investigation, but language addressing the UN Office of the High Commissioner For Human Rights' production of a progress report on human rights in Yemen was replaced with a request merely for an update on "implementation of the program of technical assistance and capacity building in the field of human rights in Yemen."

Barring negotiations reaching a unified text, a final vote on each proposal is expected at the start of October.

More than 5,000 people have been killed by all sides since the start of the coalition intervention on March 26, according to the UN. Nearly half of them — 2,355 — have been civilians, and an additional 4,862 non-combatants have been wounded. The UN's human rights chief, Zeid Ra'ad al-Hussein, has called for an independent international human rights inquiry in Yemen that would investigate violations of international law committed by all sides.

On Tuesday, Zeid's office, responding to questions raised by coalition-member Jordan, defended its human rights reporting, which has similarly indicated airstrikes are causing the majority of civilian casualties.

"Members of the High Commissioner's team in Yemen have taken considerable trouble, at great personal risk, to verify as many incidents as they can," said spokesman Rupert Colville.

Colville, quoting a report issued by Zeid earlier this month in which he called for an inquiry, acknowledged that the Office of the High Commissioner for Human Rights was "unable to verify the vast majority of allegations of human rights violations and abuses or violations of international law."

"For this reason, among others, the High Commissioner's report recommended that coalition forces and the Government of Yemen ensure prompt, thorough, effective, independent, and impartial investigations," Colville said.