Iran"s military said it will begin large-scale air defence drills on Sunday, and a cleric in the Revolutionary Guards warned that the Islamic Republic would fire missiles at "the heart of Tel Aviv" if attacked, according to Reuters. The war games, due to last five days, are intended to help protect Iran"s nuclear facilities, Iranian media reported, citing Brigadier General Ahmad Mighani. The statements came a day after senior officials from six world powers said they were disappointed Iran had not accepted proposals intended to delay its potential to make nuclear weapons, and urged Tehran to reconsider. The United States, Russia, China, Germany, Britain and France met after U.S. President Barack Obama warned there could be a package of sanctions against Iran within weeks. The United States and Israel have not ruled out military action if diplomacy fails to resolve the row over Iranian nuclear work that the West suspects is aimed at making bombs. Iran, which says its nuclear programme is solely to generate electricity, has threatened to hit back at Israel and U.S. bases in the Gulf if it is attacked. "If the enemy should want to test its bad luck in Iran, before the dust from its missiles settles in this country, Iran"s ballistic missiles would land in the heart of Tel Aviv," said cleric Mojtaba Zolnour, IRNA news agency reported. Zalnour is a deputy of Supreme Leader Ayatollah Ali Khamenei"s representative in the Revolutionary Guards, who will be staging the defence drills together with the regular armed forces. "This week"s air defence manoeuvres will be held with the intention of protecting the country"s nuclear facilities," Mighani said, Fars News Agency reported. He is the head of the armed forces" air defence headquarters. "ZIONISTS" PRESSURE" Iran often holds defence exercises and announces advances in military equipment in order to show its readiness to counter any threats over its disputed nuclear programme. IRNA, Iran"s official news agency, said the manoeuvres would take place in western Iran and that they would be "huge". Mighani also suggested Iran could itself produce an advanced missile defence system which Russia has so far failed to deliver to the Islamic state and which Washington and Israel do not want Tehran to have. Iran believes Russia"s delay in supplying high-grade S-300 missiles is due to pressure by Israel, not technical problems as cited by Moscow, Mighani said. Moscow, which is under Western pressure to distance itself from Iran over the nuclear dispute, has not followed through on proposals to ship the missiles to the Middle East country. Iranian officials have over the last few weeks voiced growing frustration at Russia"s failure to deliver the S-300. "They have declared technical problems as the underlying reason for this delay, but we think it has been due to the Zionists" pressure," Mighani said, Fars reported. "We are hopeful the Russians will ignore the pressure of the Zionist lobby." Iran, which does not recognize the Jewish state, refers to Israel as the "Zionist regime." "In various manoeuvres, new and modern missile networks will be used and evaluated, including the advanced S-300 missiles, for which the production capability exists in Iran," IRNA quoted Mighani as saying, without elaborating. A senior lawmaker, Alaeddin Boroujerdi, earlier this month also said Iran would be able to produce the S-300 system itself, appearing to refer to missiles with similar capabilities. U.S. Secretary of State Hillary Clinton praised Russia last month for not providing the missiles to Iran. The truck-mounted S-300PMU1, known in the West as the SA-20, can shoot down cruise missiles and aircraft. It can fire at targets up to 150 km (90 miles) away.