The US says it will deny or revoke visas for Palestinian officials wishing to travel to New York next month to attend the UN General Assembly session.
Secretary of State Marco Rubio blamed them for undermining peace efforts and for seeking the unilateral recognition of a conjectural Palestinian state.
The decision is unusual - the US, as host country, is expected to facilitate travel for officials of all countries wishing to visit the UN headquarters.
The ban comes as France spearheads international efforts to recognise a state of Palestine at the GA session. Donald Trump's administration has fully backed Israel in voicing opposition to such a move.
Israel's Prime Minister Benjamin Netanyahu has constantly rejected the idea of a two-state solution - the long-time international formula to resolve the decades-old Israeli-Palestinian conflict. It envisages an independent Palestinian state being created alongside Israel in the West Bank and Gaza Strip with East Jerusalem as its capital.
Netanyahu says recognition of a Palestinian state would amount to rewarding Hamas's monstrous terrorism.
The Israeli military launched a campaign in Gaza in response to the Hamas-led attack on southern Israel on 7 October 2023, in which about 1,200 people were killed and 251 others were taken hostage.
More than 63,000 people have been killed in Gaza since then, according to the Hamas-run health ministry.
Hamas has been running the Gaza Strip for years, with its rival Fatah in charge in the West Bank. Both are supposed to be governed by the Palestinian Authority (PA) led by President Mahmoud Abbas.
Abbas is also in charge of the Palestine Liberation Organisation (PLO) - the umbrella organisation which represents Palestinians at international fora. The PLO has had observer status at the UN since 1974. It can participate in meetings but not vote on resolutions.
In Rubio's announcement, he stated: Before the PLO and PA can be considered partners for peace, they must consistently repudiate terrorism - including the October 7 massacre - and end incitement to terrorism in education, as required by U.S. law and as promised by the PLO.
He added that they must also end efforts to bypass negotiations by pursuing legal cases against Israel at international courts.
Rubio reiterated that Palestinian representatives at the UN mission in New York could attend the meetings in accordance with the UN Headquarters Agreement - a document that regulates operations of the UN in the U.S. However, it remains unclear if the U.S. decision to deny or revoke visas complies with this agreement.
The state of Palestine is currently recognised by 147 of the UN's 193 member states, but the lack of clearly defined borders and ongoing settlement activities in the West Bank complicate the situation.