The U.S. will withdraw from United Nations Educational, Scientific and Cultural Organization (UNESCO), citing financial reasons and “anti-Israel bias.”

“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,” State Department spokeswoman Heather Nauert said in a statement Thursday.

The U.S. withdrawal will take effect on Dec. 31. The U.S. will remain in the cultural organization as a non-member observer.

UNESCO director-general Irina Bokova said in a statement that she wishes “to express profound regret” at the U.S.’ decision.

Nauert’s statement did not include any examples of “anti-Israel” bias, and Bokova appeared to push back at this suggestion.

She cited UNESCO’s work with “the late Samuel Pisar, Honorary Ambassador and Special Envoy for Holocaust Education, to promote education for remembrance of the Holocaust across the world as the means to fight antisemitism and genocide today.”

“Together, we work with the OSCE to produce new tools for educators against all forms of antisemitism, as we have done to fight anti-Muslim racism in schools,” Bokova added.