Israel has never confirmed or denied that it possesses atomic weapons
Israeli PM Benjamin Netanyahu has cancelled a visit to the US where he was to attend a summit on nuclear security, Israeli officials say.
Mr Netanyahu made the decision after learning that Egypt and Turkey intended to raise the issue of Israel's presumed nuclear arsenal, the officials said.
Mr Obama is due to host dozens of world leaders at the two-day conference, which begins in Washington on Monday.
Israel has never confirmed or denied that it possesses atomic weapons.
Israel's Intelligence and Atomic Energy Minister Dan Meridor will take Netanyahu's place in the nuclear summit, Israeli radio said.
More than 40 countries are expected at the meeting, which will focus on preventing the spread of nuclear weapons to militant groups.
According to Israeli officials, Turkey and Egypt are planning to call on Israel to sign the nuclear Non-Proliferation Treaty (NPT).
"These states intend to exploit the occasion in order to slam Israel," said a senior Israeli source.
BBC News, Jerusalem
Mr Netanyahu's decision is on the face of it quite odd. After all, he must have expected some focus on Israel's own nuclear programme at this conference.
Indeed, he acknowledged this possibility two days ago when he announced he would attend. He said that since Israel was not a terrorist or a rogue state, he had nothing to fear.
Certainly Israel is worried about pressure to join the Nuclear Non-Proliferation Treaty, or NPT. That is something which will increasingly become an issue since the Israelis have also announced their intention to build a civilian nuclear power station to deal with a severe electricity shortage.
But what about Israel's nuclear weapons? The former US President, Jimmy Carter, who is certainly in a position to know, has said the Israelis have at least 150 warheads.
Mr Netanyahu has said his main priority in office is dealing with Iran's supposed intentions to develop both warheads and long range missiles capable of hitting Israel. In these circumstances, Mr Netanyahu thinks it more vital than ever to protect his own weapons programme.
"The prime minister expressed his displeasure over these intentions, and he will therefore not be travelling to the summit."
Mr Netanyahu has said his main priority is dealing with Iran's supposed intention to develop both warheads and long-range missiles capable of hitting Israel.
Along with India, Pakistan and North Korea, Israel is one of just four states that have not signed up to the NPT, which has 189 signatories.
Earlier this week, President Obama unveiled the new Nuclear Posture Review - which narrows the circumstances in which the US would use nuclear weapons - outlining his country's long-term strategy of nuclear disarmament.
On Thursday, the US president and his Russian counterpart, Dmitry Medvedev, signed a landmark nuclear arms treaty in the Czech capital, Prague.
That treaty commits the former Cold War enemies to reduce the number of deployed strategic warheads to 1,550 each - 30% lower than the previous ceiling.
The BBC's Kim Ghattas in Washington says the cancellation of Mr Netanyahu's Washington visit comes at a time of frosty relations between the two states.
The Israeli premier failed to see eye-to-eye with Mr Obama during his most recent US visit last month on the stalled Israeli-Palestinian peace process, our correspondent adds.
Washington criticised the building of Jewish homes in East Jerusalem, which prompted the Palestinians to pull out of US-brokered indirect peace talks.
There were also reports that one of Mr Netanyahu's confidants called Mr Obama a "disaster" for Israel.