In a letter to nine-non profits obtained by CBS News, Secretary of State Rex Tillerson laid out his reasoning behind potentially taking the United States out of the United Nation’s Human Rights Council.

“While it may be the only such organization devoted to human rights, the Human Rights Council requires considerable reform in order for us to continue to participate,” Tillerson writes.

There are numerous countries on the council that have committed human rights abuses. These countries include China, Cuba, the Philippines and Egypt, among others. In a briefing on Wednesday, the State Department said only countries with strong human rights records should be on the Council.

“We may not share a common view on this, given the makeup of the membership,” Tillerson wrote to the organizations, which are hoping that the U.S. stays on board.

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Critics of pulling out of the council say they worry about what kind of signal quitting the Council would send to the rest of the world.

“It would be cheered by dictatorships like China, Cuba, Egypt, Russia and Iran that have been bothered by our success in using the council to highlight most serious human rights abuses around the world,” says Tom Malinowski, former State Department Assistant Secretary of State for Democracy, Human Rights and Labor. He says he expects these countries to “exploit our departure to hijack or silence the institution.”

According to critics, such a move would also be seen by allies as a particularly strange action given the recent success in taking Russia off of the Human Rights Council last year. That was considered one of the U.S. biggest successes in trying to improve the membership of the council.

The U.S. plans to participate in the ongoing session of the Council, Tillerson wrote. Among other ambitions, Tillerson said that the U.S. seeks to “reiterate our strong principled objection to the Human Rights Council’s biased agenda against Israel.”

The UN has been criticized for what critics call a bias against Israel. UN Ambassador Nikki Haley referenced that perceived bias in her confirmation hearing.

“Nowhere has the UN’s failure been more consistent and more outrageous than in its bias against our close ally Israel,” Haley said. “I will not go to New York and abstain when the UN seeks to create an international environment that encourages boycotts of Israel.”

Yet the Council’s targeting of Israel has decreased in recent years, according to a 2017 report by the Council on Foreign Relations. In 2006, 60 percent of the country-specific resolutions passed were against Israel. In 2009, when the US joined, that number went down to 40 percent and by 2016 it was down under 20 percent.

Proponents of U.S. membership in the Council say that these number show how influential American leadership is on the council in advocating for a fair-handed approach.