The U.N. atomic watchdog agency has found evidence of secret nuclear experiments in Egypt that could be used in weapons programs, diplomats said Tuesday.

The diplomats told The Associated Press that most of the work was carried out in the 1980s and 1990s but said the International Atomic Energy Agency (search) also was looking at evidence suggesting some work was performed as recently as a year ago.

Egypt's government rejected claims it is or has been pursuing a weapons program, saying its nuclear program is for peaceful purposes.

"A few months ago we denied these kinds of claims and we do so again," Egyptian government spokesman Magdy Rady said. "Nothing about our nuclear program is secret and there is nothing that is not known to the IAEA."

But one of the diplomats said the Egyptians "tried to produce various components of uranium" without declaring it to the IAEA, as they were bound to under the Nuclear Nonproliferation Treaty (search). The products included several pounds of uranium metal and uranium tetrafluoride (search) — a precursor to uranium hexafluoride gas, the diplomat said on condition of anonymity.

Uranium metal can be processed into plutonium, while uranium hexafluoride (search) can be enriched into weapons-grade uranium — both for use in the core of nuclear warheads.

The diplomat said the Vienna-based IAEA had not yet drawn a conclusion about the scope and purpose of the experiments. But the work appeared to have been sporadic, involved small amounts of material and lacked a particular focus, the diplomat said.

That, he said, indicated that the work was not directly geared toward creating a full-scale program to make nuclear weapons.

Egypt has denied in the past it is trying to develop a nuclear weapons program.

The country appeared to turn away from the pursuit of such a program decades ago. The Soviet Union and China reportedly rebuffed its requests for nuclear arms in the 1960s, and by the 1970s, Egypt gave up the idea of building a plutonium production reactor and reprocessing plant.

Egypt runs small-scale nuclear programs for medical and research purposes, and Rady said the IAEA is monitoring that program.

"Nothing about our nuclear program is secret and there is nothing that is not known to the IAEA," he said. "We don't have a secret program for energy. All our program is known."

Plans were floated as recently as 2002 to build the country's first nuclear power reactor. But no construction date has been announced, and the pro-government Al-Ahram Weekly reported late last year that the plant site near the coastal town of Al-Dabaa might be sold to make way for tourism development.

Although Egypt signed the Nonproliferation Treaty, it has become in recent years one of the treaty's most vocal critics, mainly because of concerns about Israel's undeclared nuclear arsenal and more recent fears about Iran's nuclear agenda.