Hillary Clinton said Sunday she had no regrets about vowing to obliterate Iran if it used a nuclear bomb on Israel, but Barack Obama accused her of George W. Bush-style "bluster."

The Democratic White House rivals locked horns over the Islamic republic on separate television shows, two days before their next nominating showdowns in Indiana and North Carolina.

Clinton was asked on ABC News whether she had any regrets about threatening to "totally obliterate" Iran if it used nuclear weapons against Israel, which prompted Tehran to complain to the United Nations.

(Article continues below)

"Why would I have any regrets? I am asked a question about what I would do if Iran attacked our ally, a country that many of us have a great deal of, you know, connection with and feeling for," Clinton said.

"I think we have to be very clear about what we would do," Clinton said. "I don't think it is time to equivocate about what we would do.

"I sure want to make it abundantly clear to them that they would face a tremendous cost if they did such a thing."

Full article here.