WASHINGTON - Military action against Iran could have "unintended consequences" in the region, US Defense Secretary Leon Panetta said on Thursday, hours after Tehran warned that an attack against its nuclear sites would be met by "iron fists."Panetta, who took over the Pentagon's top job in July, said he agreed with an assessment of his predecessor, Robert Gates, that a strike on Iran would only delay its nuclear program, which the West believes is aimed at making an atomic bomb.RELATED:UN chief urges diplomatic solution on Iran'China must stop trying to buy time on Iran sanctions'In confronting Iran, experts say all roads go through ChinaGates also warned it could unite the country and deepen its resolve toward pursuing nuclear weapons. Iran says its nuclear program is peaceful and that it is enriching uranium to power reactors for electricity generation."You've got to be careful of unintended consequences here," Panetta told reporters at the Pentagon, when asked about his concerns about a military strike.He acknowledged military action might fail to deter Iran "from what they want to do.""But more importantly, it could have a serious impact in the region, and it could have a serious impact on US forces in the region," he said. "And I think all of those things, you know, need to be carefully considered."
Tension over Iran's nuclear program has increased since Tuesday when the International Atomic Energy Agency (IAEA) reported that Tehran appeared to have worked on designing a bomb and may still be conducting secret research to that end.Speculation has heightened in the Israeli media that Israel may strike Iran's nuclear sites and there is speculation in the Western press about a possible US attack.Iran has warned that it will respond to any attacks by hitting Israel and US interests in the Gulf. Analysts say Tehran could retaliate by closing the Strait of Hormuz, the waterway where about 40 percent of all traded oil passes. "Our enemies, particularly the Zionist regime (Israel), America and its allies, should know that any kind of threat and attack or even thinking about any (military) action will be firmly responded to," Iran's Supreme Leader Ayatollah Ali Khamenei said on state television.