Iran on Saturday dismissed a renewed US offer of dialogue by Secretary of State Hillary Clinton, saying the "contradictions" of pursuing talks at the same time as threats undermined the proposal. Foreign Minister Ali Akbar Salehi made the comment at a joint media conference in Tehran with the visiting leader of the autonomous Kurdish region in neighbouring Iraq, Massud Barzani. Salehi was responding to remarks Clinton made on Wednesday to Farsi-language programmes on BBC Farsi and Voice of America (VOA) in which she said Washington was "prepared to engage" with Iran, even as it maintains sanctions. Salehi was quoted by Iran's state television website as saying: "We have heard such remarks a lot but unfortunately they are full of contradictions." He added that, "on one hand, they express interest in establishing relations, and on the other hand some comments are made (by the Americans) which do not jibe with that." Accusing the Americans of "arrogance", Salehi said that establishing relations would only be meaningful "when the two sides begin negotiations on an equal footing and without preconditions -- however it seems that the time (for rapprochement) has not arrived yet." The United States and Iran cut off diplomatic ties more than three decades ago, after Islamic students in Tehran took US diplomats hostage in the then-US embassy. They have been foes ever since and tensions heightened this month following US accusations of a plot by Iranian officials to assassinate the Saudi ambassador to Washington. US officials have been consulting with other countries on ratcheting up sanctions on Iran. Washington is pressing for the UN nuclear energy watchdog to condemn Iran over its controversial nuclear programme, which the United States suspects is being used to build an atomic bomb -- something Tehran denies. Clinton told BBC Farsi: "We are prepared to engage, if there is willingness on the other side, and we use sanctions... to try to create enough pressure on the regime that they do have to think differently about what they are doing." She also asserted Iran was deploying an "electronic curtain" by blocking Iranians from freely accessing many US government and foreign websites, and said "one of my highest priorities" was to provide technology and training to Iranians to circumvent the restrictions. Clinton said US efforts to open channels with Iran's government have so far been in vain. "We've tried to engage and have not yet been successful," she told VOA. "So we're looking at different sanctions, but we also continue to invite the regime to negotiate."