The United States and other laggards should ratify the nuclear test ban treaty as soon as possible, UN chief Ban Ki-Moon and others attending a nuclear conference in Vienna said Tuesday.
""We want US leadership in the CTBT ratification process," said Austrian Foreign Minister Ursula Plassnik, referring to the Comprehensive Test Ban Treaty.
She said the treaty and UN nuclear watchdog IAEA were "the pillars of nuclear non-proliferation."
UN Secretary General Ban opened the conference drawing about 100 of the 177 nations which have signed the CTBT by calling "on states which have not ratified the CTBT to do so as soon as possible."
The CTBT has now been ratified by 138 countries, including all of those in Europe. It was signed by the five nuclear powers and ratified by Britain, France and Russia but not by China and the United States.
Other countries such as Egypt, Iran and Israel have also not ratified the treaty.
Arch-rivals India and Pakistan, which have staged tit-for-tat nuclear tests, have not even signed the treaty and nor has North Korea.
Opening the conference on Monday, Ban said he hoped the October 2006 nuclear test by North Korea "will enter the pages of history as the last test ever staged."
Costa Rican Foreign Minister Bruno Stagno Ugarte, meanwhile, also urged Washington to press others into action, saying: "The key to accelerate the process remains the leadership role the United States would be ready to assume."
