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UN Secretary General Antonio Guterres was “disappointed” over the Israeli parliament vote rejecting the establishment of a Palestinian state, his spokesman said on Thursday.
And the US said it was still behind a two-state solution.
“You can't vote away the two-state solution, so the Secretary General is very disappointed by the decision of the Knesset to pass a motion opposing the establishment of a Palestinian state, west of the Jordan River,” said Stephane Dujarric.
Mr Dujarric said the solution was the only viable path to sustainable peace between Israel and the Palestinians.
The resolution was passed in the Knesset on Wednesday with 68 votes in favour and nine against in the 120-member chamber.
“The motion passed is, first, clearly inconsistent with UN resolutions, international law and prior agreements,” Mr Dujarric said.
The Israeli legislation states that a Palestinian state would pose “an existential danger to the state of Israel and its citizens, perpetuate the Israeli-Palestinian conflict and destabilise the region”.
The State Department said that US was still behind a two-state solution, and that its “approach” and “prioritisation” of it has not changed.
“The United States is committed to advancing enduring peace and security for Israelis and Palestinians alike,” State Department spokesman Vedant Patel told reporters.
"And we believe that the practical way for that is a two-state solution: a Palestinian state that is standing side by side with Israel.
“We believe that is the only way to advance an enduring peace, and it is also something that we believe is in Israel's security.”
The symbolic move by the Knesset goes against decades of international peace efforts, especially the Oslo Accords, a 1993 agreement aimed at the eventual creation of a sovereign Palestinian state alongside Israel.
The US is Israel's staunchest ally, but the resolution goes against policy under President Joe Biden and past administrations.
“I think it can be safely implied that piece of legislation that is in opposition to the two-state solution is not something that we would be thrilled about,” Mr Patel said.
The Knesset vote took place days before Prime Minister Benjamin Netanyahu is scheduled to visit Washington to address a special joint session of Congress.
Mr Netanyahu in January publicly said a two-state solution would not be possible after Israeli military operations in Gaza conclude.
Mr Biden has said he believed it could still happen.