The Norwegian-drafted resolution was adopted by the 193-member body with 137 votes in favor. Israel, the United States and 10 other countries voted no, while 22 countries abstained.
The move came in response to Israel's decision to ban the operation of the U.N. Palestinian refugee agency UNRWA in the country from late January and other obstacles faced by other U.N. agencies in their aid work in Gaza over the past year.
The ICJ, known as the World Court, is the United Nations' highest court, and its advisory opinions carry legal and political weight although they are not binding. The Hague-based court has no enforcement powers if its opinions are ignored.
The resolution adopted on Thursday also expressed "grave concern about the dire humanitarian situation in the Occupied Palestinian Territory" and "calls upon Israel to uphold and comply with its obligations not to impede the Palestinian people from exercising its right to self-determination."
The U.N. views Gaza and the West Bank as Israeli-occupied territory. International humanitarian law requires an occupying power to agree to relief programs for people in need and to facilitate them "by all the means at its disposal" and ensure food, medical care, hygiene and public-health standards.
The new Israeli law does not directly ban UNRWA's operations in the West Bank and Gaza. However, it will severely impact UNRWA's ability to work. Top U.N. officials and the Security Council describe UNRWA as the backbone of Gaza's aid response.
REPLACE UNRWA?
In a letter to the 15-member Security Council on Wednesday, Israel's U.N. Ambassador Danny Danon said that "replacing UNRWA with relief schemes that will adequately provide essential assistance to Palestinian civilians is not at all impossible."
"Israel is willing and ready to work with international partners (and already does work tirelessly) so as to allow and facilitate the continued passage of humanitarian aid to civilians in Gaza, and to ensure the unhindered provision of these necessary basic services, in a way that does not undermine Israel's security," Danon wrote in the letter seen by Reuters.
The U.N. has long-complained of aid obstacles in Gaza since the war between Palestinian Hamas and Israel began on Oct. 7, 2023. The U.N. blames Israel and lawlessness in the enclave for impediments getting aid into Gaza and distributing it to Palestinians throughout the war zone.
A committee of global food security experts warned last month that there is a "strong likelihood that famine is imminent in areas" of northern Gaza.
Israel has said the issue in Gaza was not a lack of aid because more than a million tons had been delivered during the past year. It accuses Hamas of hijacking the assistance. Hamas has denied the allegations and has blamed Israel for shortages.
Israel has long had tense relations with UNRWA, but ties have deteriorated further in the past year.
Israel says UNRWA staff took part in the Oct. 7, 2023, Hamas attack on Israel. The U.N. has said nine UNRWA staff may have been involved and have been fired. A Hamas commander in Lebanon - killed by Israel - was also found to have had an UNRWA job.