The United States is withdrawing from UNESCO because of what the Trump administration said is a "continuing anti-Israel bias" from the education and science organization.

State Department spokeswoman Heather Nauert said in a statement Thursday the U.S. would be pulling out of the United Nations Educational, Scientific, and Cultural Organization by the end of the year.

"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," Nauert said.

The State Department said it plans to "remain engaged" with the organization as a non-member.

This isn't the first time the U.S. has pulled out of UNESCO.

Former President Ronald Reagan withdrew the U.S. from the organization in 1984, and former President George W. Bush rejoined the cultural group in 2002.

In 2011, the Obama administration cut funding to UNESCO after member states admitted Palestine as a member.