A view shows the headquarters of the United Nations Educational, Scientific and Cultural Organization (UNESCO) in Paris, France, Oct 4, 2017. [Photo/Agencies]

WASHINGTON - The United States on Thursday informed the United Nations Educational, Scientific and Cultural Organization (UNESCO) that it would formally withdraw from the organization on Dec 31, 2018.

The decision reflected "US concerns with mounting arrears at UNESCO, the need for fundamental reform in the organization, and continuing anti-Israel bias at UNESCO," US State Department spokesperson Heather Nauert said in a statement.

The United States would seek to "remain engaged with UNESCO as a non-member observer state," the statement added.

The United States stopped funding UNESCO after the organization voted to include Palestine as a member in 2011. Since then, however, the United States has still maintained a UNESCO office at the organization's headquarters in Paris, France.

Meanwhile, UNESCO Director-General Irina Bokova said on Thursday that she "deeply regrets" the decision of the United States to withdraw from UNESCO.

"It's a loss to UNESCO, it's a loss to the family of the United Nations and it's a loss to multilateralism," Bokova said in a statement.

A general view shows the headquarters of the United Nations Educational, Scientific and Cultural Organization (UNESCO) in Paris, France, Oc 4, 2017. [Photo/Agencies]

Israel on Thursday welcomed US pulling out of the UN's cultural organization, announcing the Jewish state was considering a similar move due to the body's "anti-Israel" bias.

Israel's Prime Minister Benjamin Netanyahu hailed US'withdrawal as "a brave and moral decision."

A statement released by the PM's office said that Netanyahu had instructed the Foreign Ministry to prepare Israel's withdrawal from UNESCO. Israel would pull out on the same date as the US.

Netanyahu accused UNESCO of "becoming a Theater of Absurd because instead of preserving history, it twists it."

Earlier this year, UNESCO triggered Israel's anger after it listed Hebron, a city in the occupied West Bank, as a world heritage site in the "State of Palestine."

In October 2016, Israel suspended its ties with UNESCO after the organization voted in favor of a resolution that warns over the escalating violence around the holy site in East Jerusalem, a territory that Israel seized in 1967 and annexed shortly later.

Israel accused UNESCO of denying the Jewish link to the Temple Mount, a historic site destroyed in 70 AD and is nowadays a Muslim holy site called the Noble Sanctuary.