Speaking to thousands gathered in the western city of Kermanshah, President Mahmoud Ahmadinejad made his government's most extensive response so far to signs of potential changes in policy under President Obama, who has offered the possibility of diplomatic talks with Iran without preconditions in an attempt to resolve differences.

"We welcome change," Ahmadinejad said, referring to Obama's campaign mantra, "provided the change is fundamental and in the right direction."

But "if you talk of change in policies, withdraw your forces from Afghanistan," he said. "If you say change in policies, then halt your support to the uncultivated and rootless, forged, phony, killers of women and children Zionists and allow the Palestinian nation to determine its own destiny."

Iran and the U.S. remain at odds over Tehran's support for militant groups opposed to Israel and over its nuclear program, which the West alleges is aimed at making nuclear arms.

Ahmadinejad's power is superseded by that of supreme leader Ayatollah Ali Khamenei, a cleric who is Iran's highest political and religious authority. But his comments echoed recent statements by government officials and followed several days of relative official silence about Obama, suggesting they had the approval of Iran's Supreme National Security Council, a body that includes Khamenei and the country's top military and political officials.

"We will be patient," Ahmadinejad said. "We will take our time. We will scrutinize [them] under the magnifying glass, and if change takes place and it's a fundamental change, we will welcome it."

One sign of change, he added, would be for the U.S. to "apologize to the Iranian nation and try to compensate for the . . . murderous crimes which they have committed against" it.

Ahmadinejad cited the 1953 U.S.-backed overthrow of democratically elected Prime Minister Mohammed Mossadegh; Washington's support of Iraqi leader Saddam Hussein during the Iran-Iraq war; and the 1988 downing of a civilian airliner by a U.S. warship in the Persian Gulf, which killed 290.

In 2000, former Secretary of State Madeleine Albright, who served under President Clinton, acknowledged Washington's role in the coup against Mossadegh and described it as a setback for Iran's democratic development.

The U.S. eventually agreed to pay $62 million in damages to the families of the Iranian victims aboard the airliner.

Obama said in an interview with an Arab satellite news channel this week that if countries like Iran are "willing to unclench their fist, they will find an extended hand" from the U.S.