Israeli Prime Minister Benjamin Netanyahu has withdrawn from a nuclear security summit in Washington next week, fearing Muslim delegates will demand Israel give up its assumed atomic arsenal.

Netanyahu, who plans to send a deputy and two senior advisers to the April 12-13 conference instead, cancelled "after learning that some countries including Egypt and Turkey plan to say Israel must sign the NPT", an Israeli official said.

By staying outside the 1970 Non-Proliferation Treaty (NPT), Israel has not had to forswear nuclear arms nor admit international inspectors to its Dimona reactor, which experts believe has produced plutonium for between 80 and 200 warheads.

Netanyahu's attendance at the 47-country summit would have been unprecedented. Israeli premiers long shunned such forums, hoping to dampen foreign scrutiny on their nuclear secrets.

Aides said Netanyahu originally agreed to go after being reassured by the United States that the summit communique would focus on efforts to secure fissile materials and shun language challenging Israel's nuclear "ambiguity" policy.

Such coordination between the allies has been clouded, however, by rifts over stalled Israeli-Palestinian peace talks.

US President Barack Obama, who held tense talks at the White House with Netanyahu last month, scheduled no meetings with him on the summit's sidelines.

A senior Egyptian diplomat said he had no knowledge of a plan to shift attention onto Israel at the summit and accused Netanyahu of trying to evade questions on the Palestinian issue.

"We believe that Netanyahu withdrew from the summit because he did not want to face President Obama and is using Egypt and Turkey as an excuse," the diplomat said.

But the Foreign Ministry in Ankara confirmed that Turkish Prime Minister Tayyip Erdogan, who has sharply escalated criticism of Israel since last year's Gaza war, would demand at the summit that it disarm as part of a nuclear-free Middle East.

"Israel is the principal threat to peace in the region today," the French newspaper Le Monde quoted Erdogan as saying in Paris this week.

"Israel has nuclear weapons but doesn't belong to the NPT. Does that mean that those who don't sign the NPT are in a privileged position?"

Yet Egyptian and Turkish diplomats played down the prospect of the NPT coming up at the summit, saying the appropriate place would be next month's U.N. review conference on the treaty.

The White House welcomed Netanyahu's stand-in, Deputy Prime Minister Dan Meridor, to the summit. Meridor will be accompanied by Israeli National Security Adviser Uzi Arad and Shaul Horev, head of the Israel Atomic Energy Commission, aides said.

"We obviously would like to have the prime minister but the deputy prime minister will be leading the delegation and it will be a robust Israeli delegation," US National Security Adviser Jim Jones told reporters.

US-Israeli contacts are "ongoing and fine and continuous," he said.

Netanyahu had planned to drum up support at the summit for sanctions against foe Iran, which the West suspects of seeking nuclear weapons despite denials from Tehran. Neither Iran nor North Korea will be attending.

"This conference is about nuclear terrorism," Netanyahu said on Wednesday. "And I'm not concerned that anyone will think that Israel is a terrorist regime. Everybody knows a terrorist and rogue regime when they see one, and believe me they see quite a few -- around Israel."

Israel says its nuclear secrecy helps ward off enemies while avoiding the kind of provocations that can trigger arms races.

The official reticence, and the tacit US acceptance of Israel's nuclear monopoly, aggrieves Arab and Muslim powers.

India and Pakistan -- both scheduled to attend the nuclear security summit -- are outside the NPT, like Israel. Unlike them, Israel has not openly tested or deployed atomic weapons. – Reuters