The US will pull out of UNESCO, citing an anti-Israeli bias from the United Nations cultural agency, according to the State Department.

“On October 12, 2017, the Department of State notified UNESCO Director-General Irina Bokova of the U.S. decision to withdraw from the organization and to seek to establish a permanent observer mission to UNESCO,” the State Department said in a statement.

“This decision was not taken lightly, and reflects U.S. concerns with mounting arrears at UNESCO, the need for fundamental reform in the organization, and continuing anti-Israel bias at UNESCO.”

The withdrawal will become official on Dec. 31, 2018.

The US will remain involved with the United Nations Educational, Scientific and Cultural Organization “as a non-member observer state,” the State Department said.

The goal is “to contribute U.S. views, perspectives and expertise on some of the important issues undertaken by the organization, including the protection of world heritage, advocating for press freedoms, and promoting scientific collaboration and education.”

The decision to withdraw comes as UNESCO is voting to choose a new director this week amid funding troubles and divisions over Palestinian membership.

Many saw the vote to include Palestine as evidence of a long-running anti-Israel bias within the UN, where the Jewish state and its allies are far outnumbered by Arab countries and their supporters.

Team Trump has been preparing for a likely withdrawal for months, and several diplomats who were to have been posted to the mission this summer were told their positions were on hold.

Also, the Trump administration’s proposed budget for the next fiscal year contains no provision for the possibility that UNESCO funding restrictions may be lifted.

During the Obama administration, the US cut $80 million per year of its funding for the organization, a move that followed UNESCO’s admittance of Palestine, Foreign Policy magazine reported.

The cuts have increased the money owed to UNESCO to $500 million, according to the magazine.

But the Israel-Palestinian issue has been a major point of contention.

Last year, Israel removed its UNESCO ambassador after the agnecy stated that one of Jerusalem’s holy sites is specifically a “Muslim holy site of worship,” according to Reuters.

Senior American officials, including UN Ambassador Nikki Haley, have repeatedly denounced UNESCO, which the US also withdrew from during the Cold War under then-President Reagan.

Washington, which viewed the agency as mismanaged and used for political reasons, rejoined it in 2003.