By Michelle Nichols

UNITED NATIONS (Reuters) - Iran told a U.N. summit on Friday it considers nuclear terrorism to include attacking or sabotaging a nuclear facility and that as a target of such actions it places "a special importance" on preventing them.

Along with attacks on nuclear facilities, Iran said the use or threat of nuclear weapons with the intent to cause death, injury or damage to property or the environment was also deemed nuclear terrorism.

"As a country (where) not only (its) nationals have been targeted by terrorist groups, but also its nuclear facilities have been subject to cyber attacks and foreign-backed sabotage, we attach special importance to the need to prevent nuclear terrorism," said Iran's Foreign Minister Ali Akbar Salehi.

"All states have legal obligation(s) to refrain from any attack or threat of attack against peaceful nuclear facilities, whether operational or under construction, or involvement, directly or indirectly, in acts of sabotage in such facilities," he said.

Israel and the United States have both refused to rule out the possibility of an armed strike on Iran's nuclear facilities, which the West says aim to produce atomic bombs but which Tehran insists are for solely peaceful purposes. Israel has suggested it could attack Iran's atomic sites by spring 2013.

Iran believes agents working with foreign intelligence services including the American CIA and Israel's Mossad are behind the assassinations of several of its nuclear scientists. Washington has denied any role, while Israel declined comment.

"Any such act committed by a state, as certain countries continue to commit such crimes in my country, is a manifestation of nuclear terrorism and consequently a grave violation of the principles of U.N. Charter and international law," Salehi said.

"Nuclear terrorism should (not) be used as a pretext to violate the inalienable right to peaceful uses of nuclear science and technology," he said. "Any use of a nuclear weapon, whether by states or terrorists, would be catastrophic."

For nearly 10 years, Britain, France, Germany, the United States, Russia and China have negotiated unsuccessfully with Iran to persuade it to halt its nuclear program in exchange for political and economic incentives.

German Foreign Minister Guido Westerwelle told the U.N. General Assembly on Friday that Iran needed to provide a serious response to international concerns and "stop playing for time."

"We want a political and diplomatic solution. Time is short," he said. "The situation is serious."

Israeli Prime Minister Benjamin Netanyahu drew a "red line" for Iran's nuclear program on Thursday, despite a U.S. refusal to set an ultimatum, saying Tehran will be on the brink of making nuclear weapon in less than a year.

That, Netanyahu suggested, could prompt an Israeli attack by spring or summer 2013.

Iran responded by declaring it was strong enough to defend itself and that it reserved the right to retaliate with full force against any attack.

(Reporting by Michelle Nichols; editing by Christopher Wilson)