Tehran summoned the Swiss ambassador, who represents Washington's interests in Iran, on Monday to protest the latest US measures against individuals and companies for violating sanctions against the Islamic republic.

The US Treasury said last week it had blacklisted targets for "supporting Iran's nuclear programme and active support for terrorism," even as it had eased sanctions as part of an interim deal over Tehran's nuclear activities.

An official from the Iranian foreign ministry, which summoned the Swiss envoy on Monday evening, sharply criticised the United States over the measures.

"The Islamic Republic of Iran's stance on terrorism is well known and the United States, which openly supports terrorist groups in the region, is not in a position to accuse Iran.

"We strongly condemn these allegations," the official added.

The individuals and companies targeted by the US Treasury are operating in Turkey, Spain, Germany, Georgia, Afghanistan, Iran, the United Arab Emirates, and Liechtenstein.

David Cohen, the Treasury under secretary for terrorism and financial intelligence, said the US is implementing a temporary easing of some sanctions on Iran in accordance with the nuclear deal, but "the overwhelming majority of sanctions remain in effect."

The sanctions freeze any US assets of the targeted person or entity and prohibit transactions with any American.

Among the companies targeted was Spanish firm Advance Electrical and Industrial Technologies and Germany's DF Deutsche Forfait Aktiengesellschaft, for allegedly aiding Iran's nuclear and weapons proliferation activities.

The list also includes some individuals accused of plotting attacks in Afghanistan.

Under the interim deal reached in November in Geneva, Iran agreed to freeze parts of its suspect nuclear programme in return for modest sanctions relief as it negotiates a comprehensive accord.

The United States also agreed to refrain from slapping new sanctions on Iran.

Western nations have long suspected Iran of covertly seeking a nuclear weapons capability alongside its civilian programme, allegations denied by Tehran.

Iran detonators deal only a 'first step': IAEA
Vienna (AFP) Feb 10, 2014 - Iran's promise to clarify its use of detonators marks only an initial step by Tehran to address long-standing allegations of past nuclear weapons research, the UN atomic watchdog said Monday.

"This is the first step that is taking place now," International Atomic Energy Agency chief inspector Tero Varjoranta told reporters at Vienna airport after returning from Iran.

"There is still a lot of outstanding issues so now we are starting on the PMD," he said, referring to alleged "possible military dimensions" of Iran's nuclear activities, mostly before 2003.

On Sunday, Iran and the IAEA agreed a new seven-step plan to increase transparency, including a pledge by Iran to provide "information and explanations for the Agency to assess Iran's stated need or application for the development of Exploding Bridge Wire detonators".

These detonators, known as EBW's, can have "non-nuclear applications", noted IAEA said in a November 2011 report, but mostly they are used in weapons research and therefore Iran's stated development of them "is a matter of concern".

The 2011 report detailed information made available to the IAEA, much of it thought to be provided by Western and Israeli intelligence, about suspected "possible military dimensions" of Iran's programme.

More than two years of talks between the agency and Iran on addressing these claims failed to make progress. Iran denies it ever worked on nuclear weapons technology and says the evidence outlined by the IAEA is fabricated.

But following the election of Hassan Rouhani as Iranian president last year, the two sides have been trying a different approach, agreeing last November six steps which have now been completed.

Progress has also been made in parallel talks between Iran and world powers, with Iran agreeing in November in Geneva to freeze parts of its nuclear programme for six months in return for minor sanctions relief.

Talks between Iran and the six powers -- the United States, Russia, China, Britain, France and Germany -- on a long-term, "comprehensive" accord are due to start in Vienna on February 18. They are expected to last for months.