John McCain told FOX News that he didn't think President Obama was doing enough to show his support for fair elections in Iran and civil rights for Iranians after a presidential election there that "everybody knows" was corrupt.

Sen. McCain, Obama's Republican challenger in the 2008 election, suggested Wednesday in an interview with FOX News that Obama wasn't standing up for American principles.

"I'm disappointed, it is an American principle ever since our founding that we are dedicated to the principle that all are created equal and the fact is they have the right to free elections and to select their leadership," McCain said.

But Iranian leaders have accused the United States of "intolerable" meddling in its internal affairs after the country's disputed election late last week led to allegations of fraud, street protests and a government crackdown on news outlets and Web communications.

Obama said Tuesday he shared the world's "deep concerns about the election" but asserted that it was "not productive, given the history of U.S.-Iranian relations, to be seen as meddling."

And Secretary of State Hillary Clinton said Wednesday that it is up to Iranians to choose their own leader, though she didn't cast judgment on the validity of the outcome, in which incumbent President Mamoud Ahmadinejad was declared the winner.

"The people of Iran reserve the right to have their voices heard and their voices counted," Clinton said. "The result of any election should be the will of the people."

McCain argued that treading softly isn't the right approach.

"People are being killed and beaten in the streets of Tehran and all over Iran, and we should stand up for them," he told FOX News. "The way we stood up for the Polish workers in Gdansk, the way we stood up for the people of then Czechoslovakia in the Prague Spring and we have stood up for freedom in every part of the world. We're not doing that."

McCain is joining conservative Republicans in their call for the president to take a tougher rhetorical stand behind supporters of reformist presidential challenger Mir Hossein Mousavi. The reform candidate's defiant backers poured into Tehran streets for a second day, protesting that Mousavi was cheated in Friday's election.

When asked to respond to Obama's argument that perceived U.S. meddling could cast protestors as puppets of the United States, McCain said, "You know, I heard that argument during the Cold War that if we advocated for the oppressed under the then Soviet Union, that would somehow help the oppressors. It doesn't. It doesn't."

McCain also reacted to Obama's assertion Tuesday that there wasn't much difference between Mousavi and President Mahmoud Ahmadinejad.

"Well those that are being beaten in the streets of Tehran and around Iran obviously don't hold that view," he said. "So let's not take the side necessarily of the protestors...the fact is we should be on the side of a free and fair election, and not be in favor of an oppressive brutal government."