U.N. Secretary-General Antonio Guterres has urged all sides to keep fighting for the “determination of all the peoples of the world.”

Guterres said the United States and its allies are fighting against the “threat of genocide.”

In a news conference Thursday, he said, “We have no intention of allowing the situation to deteriorate.”

Gutermanns statement came a day after U.K. Prime Minister David Cameron called on the U.T.O. to end its “illegal activities” and said the U-23 World Cup team should not be allowed to play in South Africa until it is officially banned.

Cameron also called for a ban on the 2018 FIFA World Cup on home soil.

Guterre also expressed concern over the “inhumane situation” in the city of Kinshasa, where thousands of people have been killed in a crackdown by forces loyal to the president.

The U.O.’s statement, which included images of human remains and other evidence, drew criticism from human rights groups.

The Associated Press contributed to this report.