UNITED NATIONS (Reuters) - Signatories of a global anti-nuclear arms treaty -- nearly all of the world's nations -- called on Friday for a conference in 2012 to discuss banning weapons of mass destruction in the Middle East.

The creation of such a zone could ultimately force Israel to sign the nuclear Non-Proliferation Treaty and abandon any atomic weapons it has.

But U.S. officials, disappointed at efforts to single out the Jewish state, made clear the proposal might go nowhere, saying the Middle East could not be declared WMD-free until there was broad Arab-Israeli peace and Iran curbed its nuclear program.

The call came in a declaration adopted by consensus by all 189 parties to the treaty, including the United States, after a month-long meeting in New York to review the NPT that at times had seemed on the brink of failure.

The 28-page document said U.N. Secretary-General Ban Ki-moon and key states would arrange a conference that would include all nations in the region, by implication including bitter foes Israel and Iran.

At the same time, the declaration urged Israel to sign the NPT and put its nuclear facilities under U.N. safeguards, and also called on India and Pakistan, which have exploded nuclear devices, to join the pact.

The chief U.S. delegate at the meeting, Undersecretary of State Ellen Tauscher, had opposed naming Israel in the declaration, saying it undermined the idea of the 2012 conference.

But Washington ultimately acquiesced on that point.

FOCUS ON ISRAEL

Afterwards, Washington -- named as one of the co-sponsors of the proposed conference -- quickly cast doubt on its chances of ever taking place.

While welcoming agreements on a range of non-proliferation issues at the U.N. meeting, U.S. President Barack Obama said: "We strongly oppose efforts to single out Israel, and will oppose actions that jeopardize Israel's national security."

U.S. national security adviser Jim Jones criticized the "gratuitous" attention paid to Israel and said it was deplorable that the resolution failed to mention Iran as the "greatest threat of nuclear proliferation" in the region.

Israel is presumed to have a sizable nuclear arsenal but neither confirms nor denies it. It is the only Middle East state that has not signed the NPT and, like India and Pakistan, did not participate in the review conference.

Tauscher said Washington would work with countries in the region to organize a successful conference in 2012.

But she added that the U.S. ability to do that "has been seriously jeopardized because the final document singles out Israel in the Middle East section, a fact that the United States deeply regrets."

Gary Samore, who oversees policy on weapons of mass destruction at the White House, said U.S. Vice President Joe Biden had warned Arab ambassadors in Washington this week that naming Israel in the final document would be a bad idea.

"The political symbolism of mentioning Israel in this way is very destructive," he told reporters on a conference call.

"I don't know whether this conference will even happen," Samore said. "We're not going to convene a meeting unless we believe the conditions are right for having that meeting."

There was no immediate reaction from Israel.

'DIFFICULT COMPROMISE'

The White House insisted it would not put the Jewish state under any pressure nor encourage it to do anything that would undermine its national security. It also denied entering into a deal with Egypt and other Arab states on the WMD-free zone.

"There is no deal between the U.S. and Egypt or any countries with regard to that particular issue," Jones told Reuters in Washington.

Diplomats familiar with the talks, however, told Reuters the United States had agreed with the Arabs not to block consensus on the declaration while making clear it would condemn the naming of Israel.

British delegate John Duncan told the meeting the text on the Middle East had involved "difficult compromise for all parties involved."

U.N. diplomats have said that one of the reasons Washington agreed to negotiate with the Arabs on the WMD-free zone was to secure their support for new U.N. sanctions against Iran.

Tauscher said that "Iran is the only country in this hall that has been found ... to be currently in non-compliance with its (NPT) nuclear safeguards obligations."

The declaration also contained plans for further disarmament, strengthening global non-proliferation efforts and ensuring access to technology for peaceful uses.

The 1970 NPT is intended to stop the spread of atomic weapons, though it allowed the United States, Britain, France, China and Russia to keep their arsenals while calling on them to negotiate on disarmament.

The conference called on North Korea to give up nuclear weapons and return to the NPT, which it left in 2003.

(Additional reporting by Matt Spetalnick in Washington; editing by Eric Beech and Mohammad Zargham)

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