Three African nations that have said they will quit the International Criminal Court could send the wrong message about their commitment to justice, the U.N. Secretary-General said Friday.

Ban Ki-moon said that he understands concerns about the court, including how prosecutions can drag on for years, not all countries recognize the ICC’s jurisdiction and that it has only convicted Africans despite crimes in other parts of the world.

“These challenges are best addressed not by diminishing support for the court, but by strengthening it from within. Deterring future atrocities, delivering justice for victims, and defending the rules of war across the globe are far too important priorities to risk a retreat from the age of accountability that we have worked so hard to build and solidify,” Ban said.

South Africa and Burundi have already sent Ban official letters communicating their desire to leave the court. Gambia has said it plans to quit the court but the U.N. has not yet received an official letter, Ban’s spokesman Stephane Dujarric said.

The court based in the Hague, Netherlands was founded under the 1998 Rome Statute in order to prosecute war crimes, crimes against humanity and genocide. It officially opened in 2002 with the 124 member states recognizing its jurisdiction. The U.S. does not recognize the court.

Countries are allowed to leave the court one year after formally informing the U.N. of their intention.