U.N. official urges Iran to ratify test ban pact

The head of the U.N.’s nuclear test ban treaty organization challenged Iran on Tuesday to ratify the treaty as quickly as possible

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The head of the U.N.’s nuclear test ban treaty organization challenged Iran on Tuesday to ratify the treaty as quickly as possible to prove that it is serious about not wanting to develop atomic arms.

Iran and six world powers are racing to meet a June 30 deadline for a deal that would limit Tehran’s nuclear programs in exchange for the lifting of sanctions, with a renewed round to start Wednesday.

While Iranian ratification of the test ban treaty is not part of that agreement, Lassina Zerbo told The Associated Press that it would add weight to Tehran's insistence that it is not interested in such weapons.

“The CTBT bans nuclear explosions anywhere, and that’s already an assurance they could give to the international community that they are not in that process,” said Zerbo, who heads the UN's Comprehensive Test Ban Treaty Organization.

Of the CTBTO's 196 member states, 183 have signed the treaty and 164 have ratified it. But it still needs ratification of eight more of the countries involved in originally negotiating it for it to enter into force.

Its world-wide monitoring network has been up for years, however. It was among the first to detect North Korea's underground nuclear explosions and plays a key role in reporting and categorizing earthquakes and other natural disasters.

Like Iran, the United States has signed the treaty and both countries are among the eight whose ratification is needed for the treaty to become active. But the Obama administration has failed to get the needed two-thirds Senate majority for ratification.

Also among the eight is Israel, which also has signed but not ratified. Zerbo, however, dismissed suggestions that Tehran could not be expected to make the first move ahead of its two adversaries, saying doing so now would be a chance for Iran to "show great leadership ... that might help the U.S. change its position."

Zerbo said Iranian ratification should have come much earlier because with the nuclear talks in the end phase, pushing Tehran to do so now would complicate chances of reaching an agreement.

Now, he said ratification should come as a "follow-up to a deal," adding recent talks with Iranian Foreign Minister Mohammad Javad Zarif give him confidence this could happen.

Zarif wants to see an end to negotiations on a nuclear agreement before thinking of the test ban treaty, said Zerbo, but "understands that deal would make ... ratification more than relevant for Iran." He said he hopes to visit Tehran if a nuclear deal is struck to advance the issue.

Iran remains part of the CTBTO's monitoring system but turned off its seismic shock detection station in 2006. Zerbo said he has not gotten a concrete explanation from Iranian officials but thought the move was more part of negotiating tactics in the nearly decade-long nuclear talks than any indication that the Iranians were hedging on their insistence they did not want atomic weapons.