South Africa said on Friday it was quitting the International Criminal Court (ICC) because membership conflicted with diplomatic immunity laws, dealing a new blow to the struggling court and angering the political opposition, Reuters reported. The United Nations on Friday confirmed receipt of South Africa's withdrawal from the ICC, which will take effect one year from Oct. 19, spokesman Stephane Dujarric said, making it the first country to quit the Rome Statute. The instrument of withdrawal document, seen by Reuters on Thursday, has been assessed by the United Nations as bona fide and is being processed, Dujarric said. The announcement puts new pressure on the world's first permanent war crimes court, which has had to fight off allegations of pursuing a neo-colonial agenda in Africa, where all but one of its 10 investigations have been based. Burundi's leader this week signed a decree to leave the ICC, and Kenya's parliament is considering following suit. U.S. State Department spokesman John Kirby said the United States was "concerned" about the South African decision, but he declined to speculate what Kenya and Burundi would do and said it was too early to speak of a "trend" toward African withdrawal from the court.