US and Israel withdraw from UNESCO citing 'anti-Israel bias'
Israel followed suit a few hours later, with Prime Minister Binyamin Netanyahu saying the US decision was "brave and moral".
The United States was angered in 2011 when UNESCO members granted Palestine full membership, and withdrew funding from the organisation.
Washington opposes any move by UN bodies to recognise Palestine as a state, believing that this must await a negotiated Middle East peace deal.
Israel has long accused the cultural body of bias, most recently in July when UNESCO declared the occupied West Bank town of Hebron as a Palestinian World Heritage site.
US State Department spokeswoman Heather Nauert said Washington would establish an "observer mission" to replace its representation at the Paris-based agency.
The State Department notified UNESCO's outgoing Director-General Irina Bokova of their decision earlier on Thursday.
'Anti-Israel bias'
"This decision was not taken lightly, and reflects US concerns with mounting arrears at UNESCO, the need for fundamental reform in the organisation, and continuing anti-Israel bias at UNESCO," Nauert said in a statement.
The United States will "remain engaged with UNESCO as a non-member observer state in order to contribute US views, perspectives and expertise on some of the important issues undertaken by the organisation, including the protection of world heritage, advocating for press freedoms and promoting scientific collaboration and education."
The head of UNESCO Irina Bokova voiced "profound regret" on Thursday over the decision, calling it a "loss to multilateralism".
"Universality is critical to UNESCO's mission to strengthen international peace and security in the face of hatred and violence, to defend human rights and dignity," Bokova said in a statement.
"At the time when conflicts continue to tear apart societies across the world, it is deeply regrettable for the United States to withdraw from the United Nations agency promoting education for peace and protecting culture under attack."
Israel's UN ambassador, meanwhile, praised the US decision, saying it showed there was a "price to pay for discrimination against Israel".
Ambassador Danny Danon said in a statement the decision marked "a new era" at the United Nations.
"Today's decision is a turning point for UNESCO. The organisation's absurd and shameful resolutions against Israel have consequences."
The US pulled out of UNESCO in the 1980s because Washington viewed it as mismanaged and used for political reasons, then rejoined in 2003.
The administration of US President Donald Trump is reviewing a number of its multilateral commitments in pursuit of what it calls an "America First" foreign policy.
In June, Trump announced that the US was withdrawing from the Paris climate deal, throwing international efforts to combat global warming into doubt.
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