WASHINGTON: Despite Western nations tightening the screws on Iran, a top aide to President Mahmoud Ahmadinejad said increasingly tough sanctions had failed, The Washington Post reported Wednesday. On the eve of fresh negotiations with Western powers tentatively set for Dec. 5, Ahmadinejad confidant Mojtaba Samareh Hashemi said it was time for them to “stop fooling themselves” over the effectiveness of measures designed to pressure Iran into abandoning its uranium enrichment program. Banning Iranian ships from European ports, a fuel blockade against Iran Air, growing financial restrictions and other punitive measures have had “no noticeable effect,” he added in an interview with the Post. “The delay in the negotiations has been a good opportunity for the other side to realize the effects of its political decisions.” He also claimed the failure of sanctions had prompted the West to relaunch the long-stalled talks, a direct contradiction of the US position. Iran is under four sets of UN Security Council sanctions over its refusal to suspend uranium enrichment, which is at the center of fears about Tehran's atomic ambitions. It has also faced military threats and alleged technological attacks on its controversial nuclear program. Tehran and the so-called P5+1 that groups the United States, Russia, China, France, Britain and Germany have agreed to return to the negotiating table for the first time since October 2009 for a meeting tentatively scheduled to take place next month in Geneva. If Western powers do not respond to Iran's request to broaden discussions beyond its nuclear program to also discuss Israel's alleged nuclear weapons stockpile and declare they are committed to nuclear disarmament, Iran would be forced to take a harder position, Samareh Hashemi said. It would mean “they have not chosen the path of friendship,” he added. “Not answering these questions will mean they have decided not to commit to nuclear disarmament and support the Zionist regime being armed with nuclear weapons.” But the 52-year-old foreign policy expert also said Iranian negotiators will consider proposed changes to a nuclear fuel swap proposal that failed at the talks last year. Iran temporarily halted most of its uranium enrichment work earlier this month, a UN nuclear watchdog report said, an unusual move which Western diplomats said they believed was linked to technical problems. The confidential report, obtained by Reuters, did not say why or for how long Iran stopped feeding material into all centrifuge machines used to refine uranium to a low level. But it also said Iran's uranium stockpile had continued to grow and that the International Atomic Energy Agency (IAEA) remained concerned about possible activity in Iran to develop a nuclear payload for a missile. Security experts have said the release of the Stuxnet computer virus could have been a state-backed attack, possibly by Israel or another enemy of Iran, aimed at sabotaging the Islamic Republic's nuclear enrichment programme. “Was the Stuxnet worm responsible for these disruptions or were they caused by some other event or problem?” said the Washington-based Institute for Science and International Security in an analysis.