A former senator seeking the Democratic presidential nomination, John Edwards, seems to be easing back from some of his toughest rhetoric against Iran and is now speaking of the possibility of a nonaggression pact between America and Iran.

In an interview set to air on ABC’s “Nightline” last night, the 2004 vice presidential nominee was asked whether he would declare that America “will not tolerate a nuclear-armed Iran.”

“I’m just not willing to say that,” Mr. Edwards replied, according to a transcript provided by the network. “I know it’s a great question to ask a candidate or the president of the United States. … Iran having a nuclear weapon is not an acceptable thing, but the question is how do we go about, in a responsible way, preventing them from having a nuclear weapon.”

Mr. Edwards also was asked in the interview about comments he made on Saturday in New Hampshire, where, in response to a question, he reportedly said he would be open to a nonaggression pact with Iran at some juncture.

“Well, first of all, that’s way down the road. What is a good idea is to start dealing with them directly,” Mr. Edwards said in the ABC interview taped later that day. “I wouldn’t give away anything until it became clear what the intent of Iran was, that they’ve given up any nuclear ambition, that they would no longer sponsor Hezbollah, Hamas, and other terrorist organizations. … There are big issues that have to be resolved.”

Mr. Edwards repeatedly declined to discuss possible military action against Iran, or to rule it out. “It would be a foolish thing for the president to say in advance what they would do,” he said. “Under no circumstances should the president of the United States ever take anything off the table, but the issue of threats and talking about the use of force is a foolish thing to do.”

Mr. Edwards’s comments to ABC seemed somewhat less forceful than his rhetoric last month in a presentation via satellite to a conference in Herzliya, Israel, sponsored by the Institute for Policy and Strategy.

“Let me be clear: Under no circumstances can Iran be allowed to have nuclear weapons,” Mr. Edwards said then. “Iran must know that the world won’t back down. … We need meaningful political and economic sanctions. We have muddled along for far too long. To ensure that Iran never gets nuclear weapons, we need to keep all options on the table. Let me reiterate — all options must remain on the table.”

The former senator’s statements, to an Israeli audience, prompted concern and anger from left-leaning bloggers, who saw him as stoking a Bush administration effort to prepare Americans for an attack on Iran. As that furor built, Mr. Edwards detailed for one liberal blogger, Ezra Klein, the “very bad consequences” an American attack on Iran would bring.

On a different subject, Mr. Edwards told ABC he was “sad” about the recent sparring between Senators Clinton and Obama after a prominent Hollywood donor to Mr. Obama, David Geffen, referred to the President and Mrs. Clinton as liars.

In the “Nightline” interview, Mr. Edwards deftly lent credibility to Mr. Geffen’s attack, while not quite embracing it. “David Geffen’s entitled to his opinion. He’s an American. He knows a lot of the people involved,” the former senator said. “I wouldn’t say what he said, no, but I would fight forever for his right to express it.”