UNITED NATIONS (AP) -- Iran's new president said Friday that President Barack Obama struck a new tone in his U.N. speech this week that left him optimistic about easing tensions between the two countries.
Hassan Rouhani also said the recent elections that propelled him to the Iranian presidency created a "new environment" which could pave the way for better relations with the West.
Rouhani said at a news conference in New York that Iran would put forth a proposal at talks next month in Geneva on resolving the standoff over his country's nuclear program and easing international sanctions, and that he was encouraged by what he has heard recently from Western officials.
"In speaking with senior European officials and also hearing Mr. Obama ... it seemed that they sounded different compared to the past, and I view that as a positive step to the resettlement of the differences between the Islamic Republic between the Republic of Iran and the West," Rouhani said.
He said he did not meet with Obama on the sidelines of the U.N. General Assembly this week because "both sides were convinced that the timetable was too short to plan a meeting of two presidents" and at the same time "ensure that its conclusion would be solid."
Iran watchers say Rouhani may have limited time - possibly a year or less - to reach a settlement on the nuclear issue before Iran's Supreme Leader Ayatollah Ali Khamenei decides negotiations are fruitless.
In an apparent reference to resistance among hard-liners back home, Rouhani noted that "after 35 years of great tensions between Iran and the United States and a very number of issues that persist ... a meeting of the presidents for the first time will naturally come with complications of its own."
But he said Iran emerged hopeful from a lower-level meeting with the U.S. and its international partners aimed at restarting talks to settle their nuclear standoff.
"We hope that these talks will yield in a short period of time tangible results," Rouhani said.
The upbeat, if guarded, tone by both sides after Thursday's meeting of Iran, the five permanent members of the U.N. Security Council and Germany was seen as a significant step forward after months of stalled talks. It was capped by an unexpected one-on-one meeting between U.S. Secretary of State John Kerry and Iranian Foreign Minister Mohammad Javad Zarif, who shook hands and at one point sat side-by-side in the group talks.
It was the highest-level direct contact between the United States and Iran in six years.
Both sides agreed to fast-track negotiations and hold a substantive round of talks on Oct. 15-16 in Geneva. Iran, hoping to get relief from punishing international sanctions as fast as possible, said it hoped a resolution could be reached within a year.
In Vienna, meanwhile, Iranian and U.N. officials held a "constructive" meeting on resuming a probe of allegations that Tehran has worked on atomic arms, officials said Friday, in talks seen as a test of pledges by Rouhani to reduce nuclear tensions.
The upbeat assessment and an agreement to meet again Oct. 28 was a departure from the deadlock left by previous meetings over nearly two years.
At issue are suspicions outlined in reports from the U.N.'s International Atomic Energy Agency that Iran worked secretly on trying to develop nuclear weapons - something Tehran denies. As part of its probe, the agency is trying to gain access to a sector at Parchin, a sprawling military establishment southeast of Tehran.
Iran says it isn't interested in atomic arms, but the agency suspects the site may have been used to test conventional explosive triggers meant to set off a nuclear blast.
At the United Nations, Kerry said Thursday that he was struck by the "very different tone" from Iran. But along with his European colleagues, he stressed that a single meeting was not enough to assuage international concerns that Iran is seeking to develop nuclear weapons under cover of a civilian atomic energy program.
"Needless to say, one meeting and a change in tone, that was welcome, does not answer those questions," Kerry told reporters. "All of us were pleased that the foreign minister came today and that he did put some possibilities on the table."
He said they agreed to try to find concrete ways to answer the questions that people have about Iran's nuclear activities.
As the group meeting was ending, Kerry leaned over and asked Zarif: "Shall we talk for a few minutes."
A senior U.S. official said that in the one-on-one meeting, aides from both sides chatted in a marked departure from past encounters, when the Iranians were tight-lipped. It was one of the signs of a new attitude, said the official who spoke on condition of anonymity because he was not authorized to talk to the media.
The official also said Zarif presented a number of ideas - many that had come up before - but they were not particularly detailed. The Americans asked Zarif to come back at the Geneva round or even earlier with some more detailed proposals.
Zarif said the end result would have to include "a total lifting" of the international sanctions that have ravaged Iran's economy.
"We hope ... to make sure (there is) no concern that Iran's program is anything but peaceful," he said. "Now we have to see whether we can match our positive words with serious deeds so we can move forward."
British Foreign Secretary William Hague said there had been a "big improvement in the tone and spirit" from Iran compared with the previous government under Mahmoud Ahmadinejad.
Rouhani and Zarif, both in New York this week to attend the U.N. General Assembly, have said they are eager to clinch an agreement quickly that could bring relief from sanctions. The sanctions have slashed Iran's vital oil exports by more than half, restricted its international bank transfers, devalued its currency and sent inflation surging.
Encouraged by signs that Rouhani will adopt a more moderate stance than Ahmadinejad, but skeptical that the country's all-powerful supreme leader will allow a change in course, Obama has directed Kerry to lead a new outreach and explore possibilities for resolving the long-standing dispute.
Rouhani has come across as a more moderate face of the hard-line clerical regime in Tehran and his pronouncements at the U.N. have raised guarded hopes that progress might be possible. But they have also served as a reminder that the path to that progress will not be quick or easy.
He has steadfastly maintained that any nuclear agreement must recognize Iran's right under international treaties to continue enriching uranium.
The U.S. and its allies have long demanded a halt to enrichment, fearing Tehran could secretly build nuclear warheads. They have imposed sanctions over Iran's refusal to halt enrichment. Uranium enriched to low levels can be used as fuel for nuclear energy but at higher levels, it can be used to make a nuclear weapon.
Rouhani has also insisted that any deal be contingent on all other nations declaring their nuclear programs, too, are solely for peaceful purposes - alluding to the U.S. and Israel.
Those conditions underscored that there is still a large chasm to be bridged in negotiations.