(CNN) -- Sen. Barack Obama on Sunday accused Sen. Hillary Clinton of echoing the "bluster" of President Bush when she said the U.S. would be able to "obliterate" Iran if it used nuclear weapons against Israel.
Sen. Barack Obama talks with voters in Elkhart, Indiana, on Sunday, days before the state's primary.
"It's not the language we need right now, and I think it's language reflective of George Bush," Obama told NBC's "Meet the Press."
Clinton made the statement about Iran on ABC's "Good Morning America" on Tuesday.
"I want the Iranians to know that if I'm the president, we will attack Iran [if it attacked Israel]," Clinton said. "In the next 10 years, during which they might foolishly consider launching an attack on Israel, we would be able to totally obliterate them."
Not long after Obama weighed in Sunday on Clinton's remark, she was asked if she stood by her statement on ABC's "This Week."
She stuck with her message, saying warnings of "massive retaliation" are needed to keep the Islamic republic in check.
Obama and Clinton's sparring comes two days before critical Democratic primaries in Indiana and North Carolina.
Obama, addressing Clinton's statement about Iran, said, "We have had a foreign policy of bluster and saber-rattling and tough talk, and in the meantime have made a series of strategic decisions that have actually strengthened Iran."
Israel is "the most important ally" the United States has in the Middle East, and that Washington would respond "forcefully and appropriately" to any attack, Obama said Sunday.
"But it is important that we use language that sends a signal to the world community that we're shifting from the sort of cowboy diplomacy, or lack of diplomacy, that we've seen out of George Bush," he said. "And this kind of language is not helpful."
"When Iran is able to go to the United Nations complaining about the statements made and get some sympathy, that's a sign that we are taking the wrong approach," Obama said.
The Bush administration has accused Iran of working to obtain nuclear weapons, an allegation officials in Tehran deny. But Iran has ignored U.N. resolutions demanding it halt its uranium enrichment program, insisting its production of nuclear fuel is strictly for peaceful purposes.
Speaking on ABC, Clinton said U.S. leaders "have to be very clear about what we would do" in case of an Iranian attack on Israel.
"I don't think it's time to equivocate about what we would do," she said. "They have to know that they would face massive retaliation. That is the only way to rein them in."
Israel is widely believed to have its own nuclear arsenal, though it has never joined the ranks of the world's declared nuclear powers. Clinton said she did not believe Iran would attack Israel.
"But I sure want to make it abundantly clear to them that they would face a tremendous cost if they did such a thing," she stressed.
Obama and Clinton have frequently disagreed over Iran. Obama has said that in his first year as president, he would be willing to meet with the nation's firebrand president, Mahmoud Ahmadinejad, who calls for the end of Israel as a Jewish state. Clinton has said she supports diplomatic engagement -- but not at the presidential level until the Iranian leadership takes certain steps.
The two candidates also used Sunday's nearly hourlong interviews -- which, in Clinton's case, included questions from potential voters -- to address other issues dogging their campaigns.
Recent comments made by Obama's former pastor Jeremiah Wright, including alleging that AIDS was created by the federal government, made it clear to Obama that Wright "didn't know me as well as I thought he did, and I certainly didn't know him as well as I thought I did," the candidate said.
Obama said the experience regarding Wright has been "disappointing, but something that I had to clearly speak out about."
Obama added that he thinks Wright was after attention. "It's possible, as a consequence of [Wright] retiring, that having the spotlight was something attractive to him."
He also criticized Clinton's support for a "gas tax holiday," calling it "a classic Washington gimmick" that would do little or nothing to help drivers. Watch Obama and Clinton aggressively woo unions »
Clinton said it would alleviate some of the pain at the pump in the short term.
"If we actually did it right, if we had a president who used all the tools of the presidency, we would design it in such a way that it would be implemented effectively," she said Sunday.
Clinton was being interviewed on ABC by journalist George Stephanopoulos, who was part of her husband's 1992 presidential campaign.
"George and I actually were against NAFTA," she said, adding, "I'm talking about him in his previous life, before he was an objective journalist and didn't have opinions about such matters."
He then suggested she is having it "both ways" by claiming credit for NAFTA's successes while not taking "blame for the bad."
"I have said very clearly that I am going to renegotiate NAFTA and I will fix NAFTA," Clinton responded. When Republicans took control of Congress in 1995, she said, "they had a different set of priorities than the Clinton administration did."
Stephanopoulos also asked Clinton to respond to conservative radio star Rush Limbaugh's calls for Republicans to vote for Clinton as a way of keeping Democrats divided.
"He's always had a crush on me," she joked, triggering laughter throughout the room. E-mail to a friend