A former Iranian nuclear negotiator was arrested on an unspecified security charge, the Iranian state news agency reported Wednesday.

Citing an "unofficial informed source," IRNA said that Hossein Mousavian was arrested in Tehran on Monday. He was a member of the Iranian nuclear negotiator team until 2005, and also served as Iran's ambassador to Germany in late 1990s and early 2000s.

The report came as hardline President Mahmoud Ahmadinejad said Wednesday that his country would not retreat "even an iota" from its right to pursue nuclear technology.

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Mousavian was also known as a close ally of former influential President Akbar Hashemi Rafsanjani, defeated by Amadinejad in the 2005 elections. He has long been present in the international circles, negotiating on behalf of Iran with the U.N. nuclear watchdog, the International Atomic Energy Agency, and also EU leaders Germany, France and Britain.

Ahmadinejad replaced the complete Iranian negotiating team, including Mousavian, when he assumed power two years ago.

There was no official word on what the specific charge against Mousavian entailed. Usually, such charges in Iran range from violating national interests, state security interests, to treason, and carry up to life imprisonment. The cases as heard before Iran's Revolutionary Courts.

Meanwhile, Ahmadinejad said the Iranian nation would resist any attempts to curtail its rights in developing nuclear technology for peaceful, electricity-generating purposes, and would "cut off hands of invaders" if it were attacked.

"Our nation will not give up its right even an iota," the president told a crowd in Kerman city, 1,050 kilometers (650 miles) southeast of the capital, Tehran. "In the important nuclear issue, implementation of justice is the demand of Iranian nation. Our nation says, 'law for everyone, right for everyone."'

Ahmadinejad's comment came ahead of another U.N. Security Council deadline for Iran — this one in late May — to halt its uranium enrichment program or face more punishment.

The Council first imposed limited sanctions in December, then strengthened them last month because of Iran's refusal to suspend enrichment and meet a first 60-day deadline for this.

The enrichment process can produce fuel for nuclear reactors or — if taken to a higher degree — the material for atomic bombs.

Earlier in April, Ahmadinejad said additional U.N. sanctions would only prompt Iran to even further step up its nuclear development.

The U.N.'s latest sanctions ban Iranian arms exports and have frozen the assets of 28 individuals and companies involved in Iran's nuclear or ballistic missile programs. Iran has rejected the sanctions and announced a partial suspension of cooperation with the IAEA.

Tehran also in April said it had begun operating 3,000 centrifuges at its Natanz facility — nearly 10 times the previously known number. The United States, Britain, France and others criticized the announcement, but experts expressed skepticism about whether Iran's claims were true.

The U.S. and some of its allies accuse Iran of secretly developing nuclear weapons. Iran denies the charge.

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