Mohammad Khatami speaks during a news conference at Washington National Cathedral in Washington

The former president of Iran says his country may be willing to suspend its nuclear program. And, in Washington Thursday, he urged the United States to resolve its differences with Iran through dialogue, not threats.

Former Iranian president Mohammad Khatami was invited to Washington by the National Cathedral's Center for Global Justice and Reconciliation. The center's director, Canon John Peterson, said he hopes for greater dialogue between the so-called Abrahamic religions -- Judaism, Christianity and Islam.

"Even if a dialogue is not possible at this moment between our nations, certainly it is our hope that there would be more understanding between our faith communities," he said.

Mr. Khatami's speech Thursday night was scholarly and theological, and did not touch on current events.

Earlier in the day, Mr. Khatami told reporters Iran may be willing to discuss suspending its nuclear program, if the West agrees to negotiations. "We are in search of a solution. During the course of negotiations, we could even talk about suspensions, the nature of suspensions, the timing of suspensions and the duration of suspensions," he said.

The U.N. Security Council had demanded Iran suspend nuclear enrichment by August 31st. Iran says its nuclear program is for generating energy, and has refused to do so.

Iran has signed the Nuclear Non-Proliferation Treaty (NPT), and Mr. Khatami said the country is bound by NPT safeguards that ensure its nuclear program is for peaceful purposes. He pointed out that three other countries that have nuclear weapons, India, Israel and Pakistan, are not NPT signatories.

The United States has named Iran part of the so-called axis of evil and has listed Tehran as one of the world's main state sponsors of terrorism. Although the U.S. State Department is providing security for Mr. Khatami during his U.S. tour, which a spokesman said is common U.S. practice for visiting high-ranking officials, he is meeting no U.S. officials.

When asked if he is disappointed not to meet with any U.S. government representative, Mr. Khatami said he believes both sides should not blame the other side, but be ready to work to dispel historical mistrust.

"Before we can talk and engage in dialogue, we have to eliminate the language of threat," he said.

Outside the cathedral, hundreds of protesters demonstrated against Mr. Khatami's visit, shouting slogans like "human rights for Iran," and "don't support terrorism."

Other activists, like Mahnaz Afkami, executive-director of the non-governmental organization, Foundation for Iranian Studies, called Mr. Khatami a huge disappointment when he was Iran's president, from 1997 to last year. "What he did, in effect, was present a gentler, smiling face to a very authoritarian and dictatorial regime. During his time, there were more journalists in prison, there were more NGO's closed, there was a huge amount of repression," he said.

Mr. Khatami was viewed by some in the West as a reformist. He is the most senior Iranian official to tour the United States since 1979, when Iranian radicals seized the U.S. embassy in Tehran.

He has already visited Chicago. He will attend a United Nations conference in New York on Friday, and is set to speak at Harvard University on Sunday.