BEIJING, Oct. 13 (Xinhua) -- The United Nations and France have voiced deep regrets over the U.S. decision to withdraw from UNESCO, the Paris-based UN cultural organization.

The United States on Thursday informed UNESCO that it would formally withdraw from the organization on Dec. 31, 2018 and would seek to remain engaged as a non-member observer state.

Later, UN Secretary-General Antonio Guterres through his spokesperson expressed his deep regret over the decision, "considering the major U.S. role in UNESCO since its founding."

UNESCO Director-General Irina Bokova said in a statement that the U.S.withdrawal would be a loss to the United Nations and "a loss to multilateralism."

"At the time when the fight against violent extremism calls for renewed investment in education, in dialogue among cultures to prevent hatred, it is deeply regrettable that the United States should withdraw from the United Nations agency leading these issues," Bokova said.

Meanwhile, UN General Assembly President Miroslav Lajcak expressed his concerns that the U.S. move "could have adverse impacts upon the important work of UNESCO."

While emphasizing the role played by the United States in multilateral cooperation, Lajcak stressed the need for its continued engagement in the work of UNESCO.

Echoing the United Nations, France also voiced its regret over U.S. decision to withdrawal "at a time when international support for this organization is crucial."

France's Foreign Ministry Spokesperson Agnes Romatet-Espagne said "the future of UNESCO is of particular importance to France," while reiterating Paris commitment to the UN cultural agency's "critical actions" that contribute to achieving the UN goal of peace.

At the UN Headquarters in New York, French Ambassador to the United Nations Francois Delattre asked the United States not to leave UNESCO. He said "we need an America that stays committed to world affairs."

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.

According to the U.S. State Department, the decision to pull out of UNESCO reflected "U.S. concerns with mounting arrears at UNESCO, the need for fundamental reform in the organization, and continuing anti-Israel bias at UNESCO."

After the United States notified the UN organization about its move, Israel welcomed it.

Israel's Prime Minister Benjamin Netanyahu had instructed the Foreign Ministry to prepare Israel's withdrawal from UNESCO on the same date as the U.S., according to a statement.