Iranian Intelligence Minister Mahmoud Alavi said on Wednesday that four people accused of sabotaging one of the country's sensitive nuclear sites were only thieves, Mehr news agency reported.

"These four people were not saboteurs. They cut the fences and entered the area to collect scrap iron and steel and sell it on the market," Mehr quoted Alavi as saying.

"In fact, they were thieves not nuclear saboteurs," said Alavi, adding they were "villagers who had done this before".

Alavi did not specify at which nuclear site the arrests were made.

Iran's nuclear chief Ali Akbar Salehi said earlier this month that four people suspected of attempting to sabotage one of Iran's nuclear plants were arrested.

On Wednesday he said: "If the intelligence ministry... says they are thieves, then we accept it, but what an interesting thief who dug under the concrete wall and tried to enter the site."

Tehran is at loggerheads with world powers over its disputed nuclear programme, which the West and Israel suspect is aimed at making a atomic bomb despite the Islamic republic's repeated denials.

In August last year, saboteurs blew up power lines supplying Iran's underground uranium enrichment plant at Fordo outside the central city of Qom.

In 2010, a cyber-attack hit Iran's nuclear facilities. The Stuxnet virus was tailored specifically to target uranium enrichment facilities.

In recent years, Iran has detained a number of alleged US or Israeli agents accused of spying on, or attempting to sabotage, its nuclear programme.

Several Iranian nuclear engineers have also been killed in what Tehran says were assassinations by foreign intelligence services.

Iran never stopped 20 percent uranium enrichment: Salehi
Tehran (AFP) Oct 30, 2013 - Iran's nuclear chief Ali Akbar Salehi said Tehran has never stopped 20 percent uranium enrichment, denying earlier claims of a temporarily halt, parliament's website reported Wednesday.

"Twenty percent uranium and nuclear plates are being produced inside the country and there has never been a halt in the production trend," Salehi was quoted as saying.

"Nuclear plates for Tehran reactor are produced inside the country, and the needed fuel assembly is allocated for the reactor each month," said Salehi.

Earlier this month, conservative MP Hossein Naqavi Hosseini, spokesman for the foreign affairs committee, said Iran was temporarily halting enrichment to the 20 percent level.

But committee chairman Allaeddine Boroujerdi denied that on Saturday and Naqavi Hosseini later said he had been misquoted.

The enrichment programme is at the core of Iran's dispute with world powers, who suspect it masks a drive for atomic weapons despite repeated denials by the Islamic republic.

Tehran insists that 20 percent enrichment is only used for the production of the fuel needed for the research and medical reactor of Tehran.

Enriching uranium to 20 percent purity is a few technical steps short of producing weapons-grade fissile material.

Iran insists it will not bow to pressure to end enrichment despite repeated demands by the UN Security Council and several rounds of sanctions.

Demands that it be suspended were again put forward earlier this year in talks between Iran and the P5+1 group -- the United States, Britain, France, China, Russia and Germany, and Iran rejected them.

Iran is seeking the lifting of the sanctions, which have damaged its struggling economy, while world powers are seeking to ensure that Tehran is not able to develop nuclear weapons.