GENEVA — The United States and Israel have sent complaint letters to top United Nations officials contesting their staff’s impartiality over the Gaza war, documents showed, as hundreds of them protested outside the global organization’s European headquarters on Thursday.

UN staff carried placards saying “Peace for Gaza” and “Not a Target.” They laid over 370 white roses next to a memorial plaque in Geneva to represent each UN aid worker killed in the nearly two-year war.

“Today, the UN staff are coming together to say that enough is enough, to say that we cannot kill our colleagues in Gaza with such impunity and to say stop to all these murders,” Nathalie Meynet, president of the UN refugee agency staff council, told Reuters at the protest.

The letters highlight the rising tensions between the UN and its top funder, the US, which has already disengaged from the UN Human Rights Council over what Washington says is its anti-Israel stance.

A parallel vigil at the UN headquarters in New York was denied permission to proceed by management, according to a message from the organizers to UN staff seen by Reuters.

UN spokesperson Stéphane Dujarric said, “There are rules and regulations for staff to engage in activities outside of their normal activities which sometimes need to be applied.”

Israel’s Ambassador to the UN in Geneva Daniel Meron denounced the event ahead of it in a September 10 letter to Tatiana Valovaya, director-general of the United Nations’ Geneva office.

“UN staff are not activists or political actors, the letter said. “Those who incite and participate in such politically charged activities should face disciplinary measures, including suspension.”

Séverine Deboos, one of the event’s organizers, denied that its purpose was political: “The message is in honor of our colleagues (in Gaza) and to thank them,” she said.

Israel says it takes care to avoid civilian deaths in its war with Hamas.

Several hundred people joined in the protest and a minute of silence in the bright Geneva sunshine outside the UN building.

Earlier this week, a thousand UN employees joined an online briefing with Francesca Albanese, a UN special rapporteur under US sanctions who has been accused of antisemitic and pro-terror rhetoric.

Both Israel’s Meron and US Charge d’Affaires Tressa Finerty complained to Valovaya about the call in a September 16 email. She added that the matter had also been raised with UN Secretary-General Antonio Guterres.

“This is a grave violation of the UN’s principle of neutrality on multiple levels,” said Finerty.

“If UN staff during the UN workday, using UN email addresses and UN computers on UN-supplied smartphones, participate in this Teams meeting, there can be no dodging the charge that the UN is systematically and uniquely anti-Israel and, because of that, antisemitic.”

A staff union member confirmed the Albanese meeting but said it involved core UN work.

The US diplomatic mission in Geneva declined to comment.

Since the Gaza war began on October 7, 2023, with the devastating Hamas-led terror onslaught in southern Israel, some 543 aid workers have been killed in the Strip including 373 UN staff and team members, according to UN data, making the scale of losses unprecedented in the body’s 80-year history.

According to the UN, “the vast majority of those [373] casualties were personnel from the UN Relief and Works Agency for Palestine Refugees in the Near East,” or UNRWA, which Israel banned last year amid a series of revelations about employees of the agency who were actively involved in terror groups in the Gaza Strip, participation of some of its staff in the October 7 Hamas invasion and slaughter, and repeated use of UNRWA infrastructure for terror activities. Israel has also provided evidence that UNRWA schools incited hatred of Israel and glorification of attacks against Israelis.

Under Standards of Conduct for the International Civil Service adopted by the UN, staff are advised not to take sides or express their convictions publicly on controversial matters.

UN staff representatives received a management note on September 17 asking them to stay impartial on the Gaza conflict, according to a confidential memo seen by Reuters.

Under-Secretary-General for Management Strategy, Policy and Compliance Catherine Pollard acknowledged in a September 17 letter that the loss of colleagues had caused “immense suffering.”

“I want to remind you that staff associations should not organize or promote activities that may be perceived as political in nature,” the letter said, warning of risks for the organization.

“It’s not a question of neutrality,” said Yousra Ahmed, a UN staff worker at the protest. “I’m just outraged that the rules of the United Nations and humanitarian law are not being applied.”