Commissioner-general says Israeli government has undertaken a defamation campaign against the UN agency.

The UN agency for Palestinian refugees (UNRWA) has accused the Israeli government of “buying ads on Google to block users from giving donations” to the agency.

UNRWA Commissioner-General Philippe Lazzarini said in a post on X that Israel’s attempts to defame the agency both harm its reputation and put the lives of its staff at risk.

“These deliberate efforts to spread misinformation should stop + be investigated,” Lazzarini wrote on Saturday, calling for more regulations for companies, including social media platforms, to combat disinformation and hate speech.

“The spread of misinformation & disinformation continues to be used as a weapon in the war in Gaza,” he wrote.

Israel has campaigned for years against UNRWA, the main organisation delivering humanitarian aid to Palestinians in the occupied Palestinian territory and providing services for Palestinian refugees in other countries since 1949, claiming it has connections with “terrorists” and lobbying for its closure.

Last month, the UN denounced an Israeli government spokesperson after he described Lazzarini as a “terrorist sympathiser”.

David Mencer had taken aim at Lazzarini in a videotaped speech, claiming the agency had been deeply infiltrated by Hamas and Palestinian Islamic Jihad.

The UN said the comments were “reprehensible” and warned that they jeopardise Lazzarini’s safety.

Earlier this year, Israel alleged that some of the agency’s staff participated in the Hamas-led October 7 attacks on Israel, leading more than a dozen international donors to suspend support.

A UN-authorised independent review found that Israel had not provided credible evidence for its accusations and most donors have since reinstated funding.

Israeli attacks in Gaza have frequently targeted UNRWA facilities, killing 212 of its staff members and hitting at least 70 percent of its schools, according to the organisation.

At least 40,691 people have been killed and 94,060 wounded in Israel’s war on Gaza, according to according to the Gaza Health Ministry. At least 1,139 people were killed in the Hamas-led attacks on Israel, according to an Al Jazeera tally based on official Israeli statistics.