Europe

UN chief urges nuclear test ban treaty ratification

  • U.N. Secretary General Ban Ki-moon speaks during the 20th anniversary celebration of the Comprehensive Nuclear Test Ban Treaty Organization, CTBTO, at the UN headquarters in Vienna, Austria, Wednesday, April 27, 2016. (AP Photo/Ronald Zak)

    U.N. Secretary General Ban Ki-moon speaks during the 20th anniversary celebration of the Comprehensive Nuclear Test Ban Treaty Organization, CTBTO, at the UN headquarters in Vienna, Austria, Wednesday, April 27, 2016. (AP Photo/Ronald Zak)  (The Associated Press)

  • U.N. Secretary General Ban Ki-moon speaks during the 20th anniversary celebration of the Comprehensive Nuclear Test Ban Treaty Organization, CTBTO, at UN headquarters in Vienna, Austria, Wednesday, April 27, 2016. (AP Photo/Ronald Zak)

    U.N. Secretary General Ban Ki-moon speaks during the 20th anniversary celebration of the Comprehensive Nuclear Test Ban Treaty Organization, CTBTO, at UN headquarters in Vienna, Austria, Wednesday, April 27, 2016. (AP Photo/Ronald Zak)  (The Associated Press)

  • U.N. Secretary General Ban Ki-moon speaks during a press conference as part of a meeting with Austrian Foreign Minister Sebastian Kurz at the foreign ministry in Vienna, Austria, Tuesday, April 26, 2016. (AP Photo/Ronald Zak)

    U.N. Secretary General Ban Ki-moon speaks during a press conference as part of a meeting with Austrian Foreign Minister Sebastian Kurz at the foreign ministry in Vienna, Austria, Tuesday, April 26, 2016. (AP Photo/Ronald Zak)  (The Associated Press)

U.N. Secretary-General Ban Ki-moon has urged the U.S. and seven other nations to ratify the treaty banning nuclear weapons testing so that the agreement can take effect.

Ban was speaking Wednesday at 20th-anniversary commemorations of the Vienna-based CTBTO, the U.N. organization created to monitor adherence to the treaty.

But all 44 nations that participated in treaty negotiations and possess nuclear reactors must ratify the agreement before it enters into force. Besides the U.S., China, Egypt, India, Iran, Israel, Pakistan and North Korea, which has actively resumed testing, still need to do so.

Ban called on those countries "to sign and ratify the treaty without further delay."