WASHINGTON, June 10 (Reuters) - Sen. Joseph Lieberman, a long-time supporter of the Iraq war, said on Sunday military force might be necessary to stop Iran from training and equipping extremists who are killing U.S. troops. "I think we've got to be prepared to take aggressive military action against the Iranians to stop them from killing Americans in Iraq," the Connecticut independent said on CBS' "Face the Nation." "And to me, that would include a strike into -- over the border into Iran, where we have good evidence that they have a base at which they are training these people coming back into Iraq to kill our soldiers," he said. Lieberman lost the Democratic primary for re-election last year because of his support for the war but came back in the general election as an independent to be returned to the Senate. While leaving the exact nature of a military response to the generals, Lieberman said he was not talking about a massive ground invasion but more likely a strategic use of air power. Lieberman said he did not oppose talking to the Iranians, as the administration did recently in Baghdad. "If we're going to sit and talk with the Iranians, tell them what we want them to do -- which is to stop doing that (arming and training Iraqis) because it's killing Americans," he said. "They can't believe that they have immunity for training and equipping people to come in and kill Americans," Lieberman said. "We cannot let them get away with it." In the past, Lieberman has said the United States should keep a military response as a last resort in reaction to Iran's nuclear program.
