Speaking at a news conference in Tehran, Mahmoud Ahmadinejad said: "My proposal to hold a public debate with Bush remains in force."
Ahmadinejad said many issues in Iran-U.S. relations and Washington's policy in the Middle East needed to be discussed. "The United States has to understand that it must review its policy in the region," he said.
The Iranian leader last proposed a public forum with Bush during the United Nations General Assembly session in September. The White House has refused engage directly with Tehran until it suspends its uranium enrichment activities, which Washington fears could be used to build nuclear weapons.
Some U.S. officials have said Ahmadinejad's call for open debate is disingenuous considering his government's repression of free speech in Iran. The leader of the Islamic Republic remains a pariah in the U.S. due to his questioning of the Holocaust and his famous "wipe Israel off the map" comment.
At the news conference, Ahmadinejad again hailed a recent U.S. intelligence report, which said the Islamic Republic had halted its nuclear weapons program in 2003.
It represented a sharp turnaround from a previous intelligence assessment in 2005, and parallels were widely drawn with Iraq. U.S. intelligence reports on Saddam Hussein's alleged possession of weapons of mass destruction, which Washington used as grounds for invading the Middle East nation, were subsequently shown to be false.
"We believe this is a positive report, a step forward," Ahmadinejad said. "Things will change if one or two more steps forward are made."
He reiterated that Iran's nuclear program had purely peaceful goals and cited the UN nuclear watchdog's broadly positive recent report on the Islamic Republic's nuclear activities.
"With the publication of the U.S. intelligence report and that by the [International Atomic Energy Agency] IAEA chief [Mohammed] ElBaradei, no uncertainties remain regarding the Iranian nuclear issue," the president said.
Despite the U.S. report, President Bush has said Washington and its allies will continue to push for tougher sanctions against Tehran. Speaking soon after the findings were announced, Bush called for diplomacy, but did not rule out military action.
Two sets of mild UN sanctions are in place against Iran. A source in the U.S. mission to the talks on new sanctions said a draft resolution would be submitted to the UN Security Council by December 25.