The United States does not have proof that the Iranian government is responsible for military personnel and weapons smuggled into Iraq, Peter Pace, chairman of the Joint Chief of Staff, said Tuesday.

President George W. Bush said on Monday that roadside bombs in Iraq had components from Iranian and Defense Secretary Donald Rumsfeld said last week that Iranian Revolutionary Guard personnel had been inside Iraq.

"I do not, sir," Pace, a Marine Corps general, answered at a Pentagon news briefing when he was asked whether he had any proof that Iran was behind these developments in Iraq.

At the same briefing, Rumsfeld also acknowledged that he had no proof for the allegations.

"Unless you physically see it in a government-sponsored vehicle or with government-sponsored troops, you can't know it," he said.

"With respect to people, it's very difficult to tie a thread precisely to the government of Iran," he said.

Source: Xinhua