[JURIST] The US boycotted a 3-day UN conference [conference website; JURIST report] that ended Friday designed to encourage the 11 nuclear countries who have not signed the Comprehensive Nuclear Test Ban Treaty [text, PDF; Wikipedia backgrounder] to do so. Thirty-three of the 44 signatories possessing nuclear research and power capabilities have ratified the treaty, but support of the holdouts is necessary for the treaty to take effect. Of the 11 states that have refused to ratify – China, Colombia, Egypt, India, Indonesia, Iran, Israel, North Korea, Pakistan, United States and Vietnam – five (India, Pakistan, North Korea, Vietnam and Iran) joined the US in boycotting the latest round of UN talks. UN Undersecretary-General for Disarmament Nobuyasu Abe [official profile] told reporters "many speakers expressed impatience with excuses given by some countries for their failure to ratify." A declaration by all 117 nations participating said there was near-universal support for the measure, but putting it into operation was elusive because of the holdouts. The US has signed the CTBT, but it has not been approved by the Senate and it is opposed by President Bush. AP has more.