Iran warned Israel on Tuesday against attacking the Islamic state's nuclear facilities, a day after President Mahmoud Ahmadinejad raised tensions between the two foes by calling Israel the "most cruel and repressive racist regime" at a UN conference in Geneva. Israel has identified Iran as its biggest threat, citing the country's nuclear program and its development of long-range ballistic missiles. But parliament speaker Ali Larijani said if Israel attacked, "Iran will respond in a way that they will not be able to sleep easy anymore." He made the remark at a meeting in Tehran of top prosecutors from Islamic countries, who are trying to find ways to arrange for the arrest and prosecution of Israeli leaders on war crimes charges over the Gaza assault earlier this year. In response, Israeli Foreign Ministry spokesman Yigal Palmor said Israelis sleep well "and in our dreams Iran is a friendly country engaged in a constructive relationship with the international community and is not the lunatic and dangerous regime it is now."