The US has announced it will withdraw from the United Nations Scientific and Cultural Organization (UNESCO), accusing the body of "anti-Israel bias".

Heather Nauert, US state department spokesperson, said on Thursday the US would establish an "observer mission" to replace its representation at the Paris-based agency.

In a statement announcing its withdrawal, Israel called the US administration's decision "courageous and moral", and accused UNESCO of becoming a "theatre of the absurd".

"The prime minister instructed the foreign ministry to prepare Israel's withdrawal from the organisation alongside the United States," Benjamin Netayanu's office said in a statement.

Irina Bokova, the outgoing UNESCO head, called the US withdrawal a "loss to multilateralism", saying she is convinced that "UNESCO has never been so important for the US, or the US for UNESCO".

At a 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," she said.

Thursday's development demonstrates the US administration's "complete and total bias" towards Israel, says Mustafa Barghouti, secretary-general of the Palestinian National Initiative, a political party comprising mostly secular intellectuals.

"This behaviour is counterproductive and shameful," he told Al Jazeera by phone.

"Sooner or later they will see Palestine in every UN agency. Will the US respond to that by withdrawing from the WHO or the World Intellectual Property Organization? They will be hurting only themselves."

The US was angered in 2011 when UNESCO members granted Palestine full membership of the body, despite opposition from its ally Israel.

That year the US stopped paying its dues to the 195-member organisation but did not officially withdraw.

The US opposes any move by UN bodies to recognise the Palestinians as a state, insisting that this must await a negotiated Middle East peace deal.

Cultural agency

UNESCO is best known for its work to preserve heritage, including maintaining a list of World Heritage sites, and programmes to promote education in developing countries.

"UNESCO is about promoting our ideals and values through culture, education and science," Francois Delattre, France's UN ambassador, said in New York, adding that "we need an America that stays committed to world affairs."

Russia's foreign ministry said it regreted the decision, adding that the move would disrupt a number of important projects planned by UNESCO.

"We share the concern by many countries that the activity of UNESCO has been too politicised lately," the ministry said in a statement.

Antonio Guterres, the UN secretary-general, said through a spokesperson that he "regrets this development deeply".

Barghouti, of the Palestinian National Initiative, said it is "as if Israel is dictating US policy not only in the Middle East but also in international organisations.

"This is going to have a very harmful effect on the idea of the US being a mediator between the Palestinians and the Israelis."

Israel has long been at loggerheads with UNESCO, particularly over its decision to admit the Palestinians as members in 2011.

In July, the UN body declared the Old City of Hebron in the occupied West Bank an endangered World Heritage site.

Netanyahu announced a $1m cut in funding to the UN, saying the UNESCO vote ignored Jewish ties to the site.

A UNESCO resolution on Jerusalem in May strongly criticised Israel's occupation of the eastern part of the city.