WASHINGTON – Signaling a possible thaw in long-frozen relations, the Obama administration and the new leadership in Iran are communicating about Syria and are moving behind the scenes toward direct talks that both governments hope can ease the escalating confrontation over Tehran’s nuclear program.

President Obama reportedly reached out to Iran’s relatively moderate president, Hassan Rouhani, through an exchange of letters in recent weeks. The pragmatist cleric is scheduled to address the U.N. General Assembly on Sept. 24, and after years of the United States cold-shouldering his ultraconservative predecessor, U.S. officials say it’s possible they will meet with Rouhani on the sidelines.

Beyond that, U.S. and Iranian officials are tentatively laying the groundwork for potential face-to-face talks between the two governments, the first in the rancorous 34 years since radical students seized the U.S. Embassy in Tehran and founded the Islamic theocracy. Diplomatic relations have been broken ever since.

Both governments have issued conciliatory public statements in recent days that suggest a new willingness to scale back the tension. Obama suggested in four TV interviews this week, for example, that Iran had played a constructive role in pushing Syrian President Bashar Assad to refrain from using chemical weapons.

“You know, one reason that this may have a chance of success is that even Syria’s allies, like Iran, detest chemical weapons,” Obama told CNN. “Iran, you know, unfortunately was the target of chemical weapons at the hands of Saddam Hussein back during the Iraq-Iran War. ...”

The United States and Iran have exchanged private messages about the civil war in Syria, according to Iran’s new foreign minister, Mohammad Javad Zarif, although he didn’t reveal the substance. Analysts say Iran is trying to avoid having the Syrian chemical weapons crisis damage prospects for a potential resolution of Tehran’s nuclear standoff with the West.

Zarif’s prominent role marks a clear shift in Tehran. The graduate of San Francisco State University and the University of Denver, and a popular diplomat when he was Iran’s envoy to the United Nations from 2002 to 2007, has been named to lead Iran’s nuclear negotiating team.

Rouhani was elected in June after promising voters he would allow greater personal freedom and strengthen the economy. Since he took office, Iran has scaled back its anti-Western invective and muted the Holocaust denials associated with the previous president, Mahmoud Ahmadinejad. In perhaps the most jaw-dropping sign of change, Rouhani apparently sent a tweet this month wishing Jews a happy Rosh Hashana, the Jewish new year.

White House officials said Wednesday that they wouldn’t confirm or comment on Obama’s private correspondence. But Bernadette Meehan, a spokeswoman for the National Security Council, said the administration was ready to talk if Iran was serious.

Rouhani’s election “presents an opportunity for Iran to act quickly to resolve the international community’s deep concerns over Iran’s nuclear program,” Meehan said. “Should this new government choose to engage substantially and seriously to meet its international obligations and find a peaceful solution to this issue, it will find a willing partner in the United States.”