DUBAI - Iran's foreign minister said on Saturday that accusations about activity at its Parchin military site were "lies" spread by opponents of its landmark nuclear deal with world powers clinched last month.

A prominent U.S. think-tank on Friday questioned Tehran's explanation for activity at its Parchin military site visible in satellite imagery, saying the movement of vehicles did not appear related to road work. "We said that the activities in Parchin are related to road construction," Foreign Minister Mohammad Javad Zarif was quoted on Saturday as saying by the IRNA state news agency.

"They (opponents of the deal) have spread these lies before. Their goal is to damage the agreement," he added. Parchin is a site to which the U.N. nuclear watchdog, the International Atomic Energy Agency (IAEA), requested access as part of the July 14 nuclear accord between Iran and six major powers, which include the United States.

The U.S.-based Institute for Science and International Security suggested Iran could be engaged in cleanup work before IAEA inspectors arrive at the site. The speaker of Iran's parliament also dismissed the think-tank's suggestions. "This is an artificial dispute to distract the world. There are some movements at Parchin but trying to expand those activities to the military facility and making a fuss about it is like some fairy tale," Ali Larijani was quoted on Saturday by the Fars news agency as saying.

"Israelis are not happy about the deal and they will do anything to stop it," he added. Israeli Prime Minister Benjamin Netanyahu has been pushing U.S. lawmakers to oppose the nuclear agreement, which he considers a threat to his country's survival. Some pro-Israel groups have been spending millions of dollars on an advertising campaign to persuade members of the U.S. Congress to reject the deal in the autumn.

In the meantime, Iran's military chief and a close ally to the Supreme Leader expressed his support on Saturday for the country's nuclear deal with world powers, a key endorsement for the accord that faces strong opposition from hardliners.

Conservative members of the Iranian parliament and chief commander of the elite Revolutionary Guards, Mohammad Ali Jafari, have sharply criticised the deal, saying it undermined the Islamic Republic's military capabilities. While Supreme Leader Ayatollah Ali Khamenei has not publicly approved or disapproved of the deal, he has told officials and experts to take legal procedures to ensure the other side does not breach it, saying some of the world powers involved were untrustworthy.

Major General Hassan Firouzabadi listed 16 "advantages" to the deal, which Iran signed in Vienna in July, without detailing any drawbacks. "The armed forces have the most concerns about the effect of the deal on Iran's defence capabilities but this agreement and the U.N. Security Council resolution have many advantages that the critics ignore," Firouzabadi was quoted as saying by Fars News Agency.

The agreement, a major initiative for both US President Barack Obama and Iran's pragmatic President Hassan Rouhani, has been met with resistance from hardliners in both countries. "The tone of the U.N. Security Council resolution has changed compared to the previous ones. Regarding Iran's missile activities, it doesn't order but only asks for Iran's compliance," Firouzabadi said, referring to an international resolution passed in the wake of the deal.

Iran's procedures for ratifying the accord are not known in any detail. Whatever the eventual role of parliament or the National Security Council, the deal will have to be approved by Khamenei, the country's highest authority.