He also said, however, that any investigation into Iran's disputed election, which has led to protests and violence, must come without bloodshed. Mr. Obama maintained that "the democratic process, free speech, the ability of people to peacefully dissent" are universal values that must be respected, reports CBS News White House correspondent Mark Knoller.
The president added that people are "rightfully troubled" by images of violence against peaceful protesters and that "it would be wrong to stay silent" about the protests.
To the people in Iran upset by the election results, Mr. Obama said "the world is watching and inspired by the participation."
The president said the situation did not change his intention to negotiate without precondition with the Iranian leader.
"I have always felt that, as odious as I feel some of President Ahmadinejad 's statements [are], as deep as the differences that exist between the United States and Iran on core issues, the use of tough hard headed diplomacy, diplomacy without illusions, is critical when it comes to pursuing a core set of national security interests," he said. "…We will continue to pursue a tough direct dialogue between our two countries."
Mr. Obama said he could not comment on voting fraud allegations, noting that the United States did not have observers watching the election first hand.
The president has been criticized by Republicans for not discussing the fallout from the reelection of incumbent President Mahmoud Ahmadinejad, which critics say is illegitimate. He made the comments following a White House meeting with Italian Premier Silvio Berlusconi.