The US criticised "the breadth" of the top UN court's opinion that Israel's occupation of Palestinian territories is illegal, with Washington saying it would complicate efforts to resolve the conflict.
"We have been clear that Israel's program of government support for settlements is both inconsistent with international law and obstructs the cause of peace," a US State Department spokesperson said on Saturday in an email.
"However, we are concerned that the breadth of the court's opinion will complicate efforts to resolve the conflict," the State Department added.
The International Court of Justice, or the World Court, said on Friday that Israel's occupation of Palestinian territories and settlements was illegal and should be ended as soon as possible, delivering its strongest findings to date on the Israeli-Palestinian crisis.
The State Department said the ICJ opinion that Israel must withdraw as soon as possible from the Palestinian territories was "inconsistent with the established framework" for resolving the conflict.
Washington said that framework took into account Israel's security needs, which it says were highlighted by the October 7 attack in southern Israel led by Palestinian group Hamas. That surprise attack killed around 1,190 people, with around 250 people taken as hostages, according to Israeli tallies.
Hamas says the attack came in response to Israel's decades-long occupation of Palestine and aggression against the Palestinian people.
Israel's blistering war on Gaza since October 7 has devastated the enclave and has killed almost 39,000 people, mostly civilians. The offensive, Israel's biggest ever, has caused a hunger crisis in the Palestinian enclave and has displaced most of the its 2.3 million population.
Two-state solution
The advisory opinion by ICJ judges is not binding but carries weight under international law and may weaken support for Israel.
The State Department said the way forward was through direct negotiations.
"Israeli settlements in the West Bank and East Jerusalem, and the regime associated with them, have been established and are being maintained in violation of international law," ICJ President Nawaf Salam said on Friday while reading the findings of a 15-judge panel.
The court said Israel's obligations include paying restitution for harm and "the evacuation of all settlers from existing settlements".
Israel rejected the opinion and said a political settlement can only be reached through negotiations. The office of Palestinian President Mahmoud Abbas welcomed the opinion, which it called historic.
The State Department said it "strongly discourages" parties from using the ICJ opinion "as a pretext for further unilateral actions that deepen divisions or for supplanting a negotiated two-state solution."
The ICJ case stems from a 2022 request for a legal opinion from the United Nations General Assembly. It predates Israel's war on Gaza.
The ICJ opinion said the UN Security Council, the General Assembly and all states have an obligation not to recognise the occupation as legal nor "render aid or assistance" toward maintaining Israel's presence in the Palestinian territories.
Israel captured the West Bank, Gaza Strip and East Jerusalem - which the Palestinians want for a state - in the Six-Day War in 1967 and has since built and expanded settlements in the West Bank.