Iran's top leader Ayatollah Ali Khamenei threatened on Sunday that Iran would disrupt energy shipments from the Gulf region should the country come under attack from the US, insisting that Teheran will not give up its right to produce nuclear fuel. "If you make any mistake (invade Iran), definitely shipment of energy from this region will be seriously jeopardized. You have to know this," Khamenei said in a speech broadcast live on state-run radio. Khamenei also warned that the US and its allies would not be able to provide security to all the oil shipments that cross the strategic Hormuz Strait - within close range of Iran - should a disruption occur. "You will never be able to protect energy supply in this region. You will not be able to do it," he said, addressing the West. Khamenei, however, did not specify how oil supplies would be disrupted, and insisted Iran would not start any war. "We won't be the initiator of war," he said. Iran is the world's fourth largest oil exporter and second biggest power within the Organization of Petroleum Exporting Countries. Iranian officials have repeatedly ruled out using oil as weapon in the nuclear standoff with the West. Khamenei's harsh rhetoric came a day after Iranian President Mahmoud Ahmadinejad said a breakthrough in negotiations over Tehran's contentious nuclear program was possible and welcomed unconditional talks with all parties, including the United States. In Russia, Foreign Minister Sergey Lavrov also welcomed the US offer of direct talks with Iran. "If it becomes possible to resolve the problem through direct bilateral talks between Iran and the United States, nobody will be distressed," the Russian minister was quoted as saying by the Rossiya state television on Sunday. Ahmadinejad said late Saturday that his government would not rush to judge an incentives package offered by Western countries to persuade Iran to cease enriching uranium. Khamenei appeared to be taking a tougher line Sunday. "That a country has no right to achieve proficiency in nuclear technology means it has to beg a few Western and European countries for energy in the next 20 years," he said. "Which honest leader is ready to accept this?" Khamenei said Iran was not a threat to any country and that Tehran was not seeking nuclear weapons. "We have not threatened any neighbor ... accusation that we are seeking nuclear bomb is wrong, a sheer lie," he said. "We have no target to use a nuclear bomb. It's against Islamic teachings," said Khamenei. President Ahmadinejad has however repeatedly questioned Israel's right to exist and said the country should be wiped off the map. Khamenei insisted Sunday that the production and maintenance of an atomic bomb would "impose a lot of irrelevant costs," and that a state like Iran did not need such a weapon. "Unlike the US, we have no claim to dominate the world," he added. The supreme leader told his nation that pressure on Iran to cease nuclear research stemmed solely from the US and its close allies. Khamenei said Iran had "sound and good relations" with Europe, as well as with the Arab world and Russia. "There is no consensus against Iran. This is a lie by the US and few other US supporters," he said. "Some 116 member states of the Non-Aligned Movement supported Iran's brave achievements in nuclear technology," Khamenei said, referring to a support motion passed at a NAM meeting in May. NAM, the world's biggest bloc after the United Nations, comprises mostly developing countries and anti-US nations such as North Korea and Cuba. Its support motion to Iran is purely moral. "Consensus is among a few monopolist countries. Their consensus is of no value," insisted Khamenei. His comments came as European Union diplomacy chief Javier Solana was expected in Tehran to hand deliver the new package of incentives for Iran to give up uranium enrichment, or sanctions if it refuses. The plan could either defuse a global confrontation with the Islamic regime or hasten one. The package, agreed upon Thursday by the five permanent members of the U.N. Security Council and Germany, carries the threat of U.N. sanctions if Tehran remains defiant over its nuclear program, which the West fears is a cover for producing nuclear weapons. Iran says it is only striving to use nuclear reactors for generating electricity. Specific measures have not been mentioned, but US officials said privately that Iran could face tough Security Council sanctions if it refuses to give up uranium enrichment and other disputed nuclear activities. Earlier Sunday, a news report said that Japan is considering imposing sanctions on Iran if it continues to reject international calls to scrap its nuclear program and controversial uranium enrichment efforts. The sanctions would ban the remittances of money to Iran from Japan, the Yomiuri newspaper said, citing unidentified sources. Japan has tried to seek a diplomatic solution to the standoff over Iran's nuclear ambitions, but with Iran still uncommitted to a package of incentives offered by other nations, the Japanese government is considering stronger measures, the report said. Chief Cabinet Secretary Shinzo Abe, when asked about Iran on a Sunday morning talk show, declined to say whether Japan was considering sanctions and said the government is still pushing for a diplomatic resolution.