VIENNA (AP) — The head of the U.N. atomic watchdog is asking for international input on an Arab-led push to have Israel join the Nonproliferation Treaty, in a move that adds to pressure on the Jewish state to disclose its unacknowledged nuclear arsenal.

Israel, in turn, is suggesting efforts should focus instead on giving teeth to the nuclear treaty to prevent signatories like Iran from acquiring such weapons.

On Wednesday, The Associated Press disclosed that International Atomic Energy Agency chief Yukiya Amano had sent a letter soliciting proposals from the agency's 151 member states on how to persuade Israel to sign the treaty. And the world's five recognized nuclear-weapons powers — the U.S., Russia, Britain, France and China — reaffirmed the goal of a nuclear-free Middle East.

A string of Israeli officials, including a spokesman for Prime Minister Benjamin Netanyahu, the minister of atomic energy, the deputy minister of foreign affairs, the minister of strategic threats and the minister of communication, all refused to comment on the recent developments.

The latest pressure is putting the Jewish state in an uncomfortable position. It wants the international community to take stern action to prevent Iran from getting atomic weapons but at the same time brushes off calls to come clean about its own nuclear capabilities.

In his letter, Amano asked foreign ministers of the IAEA's 151 member states to share views on how to implement a resolution demanding that Israel "accede" to the Nonproliferation Treaty and throw its nuclear facilities open to IAEA oversight.

In response Thursday, an Israeli government official noted that the treaty obligating nations to stop the spread of nuclear weapons didn't stop countries like Saddam Hussein's Iraq and now Iran from pursuing nuclear weapons programs. Iran denies that accusation, which has also been made by the U.S. and other world powers. The Israeli official spoke on condition of anonymity in keeping with his country's opaque nuclear policy.

Egypt has proposed that a Nonproliferation Treaty conference now meeting at U.N. headquarters in New York back a plan calling for the start of negotiations next year on a Mideast free of nuclear arms.

The U.S. has cautiously supported the idea while saying that implementing it must wait for progress in the Middle East peace process. Israel also says a comprehensive Middle East peace settlement must come first.

"The question is, how do you do that in the absence of a peace plan?" Undersecretary of State Ellen Tauscher said Wednesday of the "nuke-free" zone idea.

Still, Washington and the four other nuclear weapons countries recognized as such under the NPT appear to be ready to move from passive support to a more active role.

In her speech to the U.N. nuclear conference on Monday, Secretary of State Hillary Rodham Clinton said Washington would support "practical measures for moving toward that objective," while Tauscher said the U.S. has been working "for months" with Egypt on the issue.

Washington also has been discussing it with the Israelis, said another Western diplomatic source, who asked for anonymity since he was discussing other countries' contacts.

Russian arms negotiator Anatoly I. Antonov, speaking on behalf of the five NPT nuclear powers, said these nations were "committed to full implementation" of a Middle East nuclear free zone.

Amano's April 7 letter comes seven months after IAEA member states at their annual Vienna conference narrowly passed a resolution directly criticizing Israel and its atomic program, with 49 of the 110 nations present in support, 45 against and 16 abstaining.

The result was a setback not only for Israel but also for Washington and other backers of the Jewish state, which had lobbied for 18 years of past practice — debate on the issue without a vote.

The resolution "expresses concern about the Israeli nuclear capabilities," and links it to "concern about the threat posed by the proliferation of nuclear weapons for the security and stability of the Middle East."

The U.S. and its allies consider Iran the region's greatest proliferation threat, fearing that Tehran is trying to achieve the capacity to make nuclear weapons despite its assertion that it is only building a civilian program to generate power.

But Islamic nations insist that Israel's nuclear capacity is the true danger in the Middle East.

With divisions deep, Amano's letter foreshadowed intense feuding at that September conference.

"It would be helpful to me if Your Excellency could inform me of any views that your government might have with respect to meeting the objectives of the resolution," according to his half-page letter.

A senior diplomat from one of the IAEA member countries confirmed that his government had received the letter. He and an official from another IAEA delegation said that to their knowledge the agency was still awaiting responses. Both asked for anonymity because their information was confidential.


Associated Press writers Amy Teibel in Jerusalem and Charles Hanley at the United Nations contributed to this report.