Lebanon's Iranian-backed militant group, Hezbollah, stated on Monday that Iran could hit U.S. bases in the Middle East, should Israel attack its nuclear facilities.
Even if U.S. forces play no role in an attack on Iran, the Hezbollah leader says U.S. bases could be attacked.
Hezbollah Secretary-General Sayyed Hassan Nasrallah, told Al Mayadeen television in Beirut, "A decision has been taken to respond and the response will be very great."
Citing information Nasrallah said was from Iranian officials, he added "The response will not be just inside the Israeli entity - American bases in the whole region could be Iranian targets. If Israel targets Iran, America bears responsibility."
Israel is thought to be the only nuclear-armed power in the Middle East and views Iran's nuclear program as a threat, while Tehran insists that the program is for peaceful purposes only, and has recently opened Iran's first nuclear power plant in Bushehr.
On Sunday, Israel Prime Minister Benjamin Netanyahu urged world powers to set a "clear red line" in order to convince Iran to stop its nuclear program.
Meanwhile, Netanyahu's cabinet in divided over attacking Iran. Some Israeli officials have hinted at a "climbdown strategy", under which the prime minister would shelve threats of an attack on Iran, hoping for a stronger pledge from the U.S. government on their possible future action in Iran.
According to Nasrallah, there are divisions in Israel over an Iranian attack. He said, "Personally I do not expect the Israeli enemy - at least in the coming months or foreseeable future - (to wage) an attack on the Islamic Republic of Iran."
Referring to the current fragile global economy, which would be weakened further by sharp increases in crude oil prices resulting from a conflict in the Gulf, he said, "Netanyahu and (Defence Minister Ehud) Barak inflate the benefit and play down the cost."
He also made reference to Defence Minister Ehud Barak's estimates that Israel could suffer up to 500 fatalities from any conflict, aimed at destroying Iran's nuclear facilities.
Nasrallah spoke of the 34-day war with Israel six years ago, when 1,200 people in Lebanon (mainly civilians) and 160 people in Israel (mostly soldiers) were killed.
He said that war with Iran would be more deadly, "We don't know what will happen in the region."
Nasrallah also denied that Shi'ite Islamists would ever use chemical weapons in the conflict. "We do not have chemical weapons and we will not use chemical weapons. The use of chemical weapons is forbidden - for us that is absolute," he said.
Addressing Israel, Nasrallah said, "I do not need chemical weapons - regardless of the religious or practical position. You have factories, and you have bases, and compounds, and I have rockets."
He stated that Israel had several "weak points" which could be targeted. These include "economic, industrial, electrical, chemical and nuclear" sites, he said.
He said that even if Israel launched a first strike attack on Lebanon, thus destroying most of Hezbollah's missile arsenal, the group would still have the capacity to strike back with deadly force. He said two weeks ago that Hezbollah could kill tens of thousands of Israels with precision-guided missiles.
"Hitting these targets with a small number of rockets will turn ... the lives of hundreds of thousands of Zionists to real hell," he added.