U.S. President George W. Bush personally signed off on a visa allowing former Iranian president Mohammed Khatami to visit the United States because he wanted to hear his views, the Wall Street Journal reported Saturday.

Khatami, Iran's president from 1997 to 2005, is the most prominent Iranian in decades to visit the United States, outside of the United Nations' New York headquarters.

His five-city speaking tour is controversial given U.S. accusations that Iran is pursuing nuclear weapons, sponsors terrorism and arms Hezbollah guerrillas in Lebanon.

"I was interested to hear what he had to say," Bush told the Wall Street Journal in an interview. "I'm interested in learning more about the Iranian government, how they think, what people think within the government."

Khatami, viewed as a reformist, ceded power last year to current President Mahmoud Ahmadinejad, a conservative who has called for Israel to be "wiped off the map" and has been an outspoken critic of U.S. policies.

"My hope is that diplomacy will work in convincing the Iranians to give up their nuclear weapons ambitions. And in order for diplomacy to work, it's important to hear voices other than Ahmadinejad's," Bush added.

Khatami has stressed themes of dialogue and coexistence during his U.S. tour, which includes a speech he gave at the Washington National Cathedral on Thursday and an appearance Sunday at Harvard University.