"One of the concerns people have is that Israel might do it without being asked," Cheney, who led the chorus of voices calling for Saddam Hussein's ouster ahead of the March 2003 invasion of Iraq, told MSNBC in an interview.

"Given the fact that Iran has a stated policy that their objective is the destruction of Israel, the Israelis might well decide to act first, and let the rest of the world worry about cleaning up the diplomatic mess afterwards," he said.

The vice president said he was "very concerned" about Iran's nuclear program, which Tehran says is for the purpose of civilian energy production but Washington charges is cover for a nuclear weapons program.

He also said Iran was "a noted sponsor of terror" pointing to Tehran's support for Hezbollah, and said "that combination is of great concern."

"You look around the world at potential trouble spots, Iran is right at the top of the list," said Cheney. "We'll continue to try to address those issues diplomatically, continue to work with the Europeans."

But he downplayed the likelihood of US military action, saying: "In the case of the Iranian situation, I think everybody would be best suited by or best treated and dealt with if we could deal with it diplomatically."