(JTA) — The Trump administration is threatening to withdraw from the U.N. Human Rights Council, citing among other things the intergovernmental body’s “biased agenda against Israel.”

Secretary of State Rex Tillerson sent a letter this week to nine nonprofit groups opposed to withdrawal — including one affiliated with the American Jewish Committee — in which he explained that the United States may quit the council unless it makes reforms, Foreign Policy reported.

In the meantime, Tillerson said the U.S. would “reiterate our strong principled objection to the Human Rights Council’s biased agenda against Israel.”

Tillerson wrote that the U.S. was concerned as well about the council membership of countries accused of human rights violations, such as China, Egypt and Saudi Arabia.

The nine groups, which include the AJC-affiliated Jacob Blaustein Institute for the Advancement of Human rights, wrote a letter last month to Tillerson arguing that the U.S. can better protect Israel from disproportionate criticism if it remains a member, according to Foreign Policy.

The Obama administration rejoined the Human Rights Council in 2009 after the Bush administration had withdrawn, partly as a means of exerting influence and partly because the U.S. presence might mitigate some of the council’s harsh criticism of Israel.

Israel and its supporters have accused the Human Rights Council of disproportionately targeting the Jewish state with criticism while overlooking abuses by other countries. From the council’s creation in June 2006 through June 2016, over half of its resolutions condemned Israel, according to U.N. Watch, a watchdog that monitors criticism by the United Nations of the Jewish state.

Last week, Israeli Defense Minister Avigdor Liberman asked the Trump administration to pull out of the Human Rights Council and conduct a review of the United Nations Relief and Works Agency for Palestine Refugees.

The groups “do not fulfill the roles assigned to them,” Liberman told Tillerson, according to an Israeli Defense Ministry readout of the meeting, which took place March 8 in Washington, D.C.

Last month, Politico reported that the Trump administration was considering pulling out of the Human Rights Council.