In his speech at the annual General Assembly, Mr. Netanyahu dramatically illustrated his intention to shut down Iran's nuclear program by drawing a red line through a cartoonish diagram of a bomb. But the substance of his speech suggested a softening of what had been a difficult dispute with the Obama administration on how to confront Iran over its nuclear program.

Only two weeks after that dispute broke into the open, Mr. Netanyahu on Thursday praised the warning Mr. Obama gave Iran in his own General Assembly speech on Tuesday.

"I very much appreciate the president's position, as does everyone in my country," he said. The Israeli leader's speech also suggested that his deadline for a military strike was well past the American presidential election and into 2013 — perhaps as late as next summer.

Mr. Netanyahu said in an interview on "Meet the Press" on NBC that was broadcast on Sept. 16 that he believed Iran was six months from amassing most of the enriched uranium needed for a bomb. "You have to place that red line before them now," he said. But his speech on Thursday was more explicit about his time frame for a military strike.

While such a strike seemed like a receding possibility in recent weeks, it had remained a possible "October surprise" that worried the White House and military planners.

Mr. Netanyahu's softened tone may also have also reflected Israel's reading of the American presidential polls, which have shown Mr. Obama's lead widening somewhat since the prime minister's harsh words in mid-September, when he said the United States had no "moral right" to hold back Israel from taking action against Iran because the Obama administration refused to set its own red line.

"It seems that Netanyahu's Iran policy is becoming more Obama-friendly," Meir Javedanfar, an Iranian-Israeli lecturer at the Interdisciplinary Center in Herzliya, Israel, said in an e-mailed reaction to Mr. Netanyahu's speech.

"What was most impressive was that he drew a red line, without committing himself to it," Mr. Javedanfar said. "He also did it in a way which takes the pressure off Obama, illustrated by the fact that he pushed back the timelines to next year."

Michael Herzog, a former chief of staff to Israel's defense minister and an Israel-based fellow at the Washington Institute for Near East Policy, said it was implicit in Mr. Netanyahu's remarks that "there are six or seven months more to continue to pressure the Iranians. The international buzz before was that Israel had to act before the November elections."

Mr. Netanyahu's speech also came against a backdrop of revived international diplomacy with Iran, which has insisted its nuclear program is peaceful. Foreign ministers from the so-called P5-plus-1 group of countries — the five permanent members of the Security Council plus Germany — met to discuss how to advance negotiations with Iran that have been stalled since June.

"All of the ministers were unified in their belief that diplomacy is the much preferred way forward," a senior Obama administration official said after the meeting.

A new report by Israel's Foreign Ministry calls for another round of sanctions against Iran, seemingly another acknowledgement by the Israelis that there might be time to stop its rival's nuclear program by means other than military action.

The report, published on Thursday by the newspaper Haaretz, states that the international sanctions already imposed are having a deep effect on Iran's economy, and may, according to some assessments, also be affecting the stability of the Iranian government. But because the sanctions have not persuaded Tehran to suspend the program, the report concludes, "another round of sanctions is needed."

Rick Gladstone reported from New York, and David E. Sanger from Washington. Jodi Rudoren and Isabel Kershner contributed reporting from Jerusalem, and Steven Lee Myers from New York.

This article has been revised to reflect the following correction:

Correction: September 27, 2012

An earlier version of this article misidentified at one point that day on which Prime Minister Netanyahu addressed the United Nations.
As the article noted correctly elsewhere, it was Thursday, not Wednesday.

This article has been revised to reflect the following correction:

Correction: September 27, 2012

An earlier version of this article misspelled the Israeli city where the Interdisciplinary Center is located. It is Herzliya, not Herzilya.