Gee, Mr. President. Ya think?

President Obama, whose campaign for the White House included a pledge to open talks with Iran, said Friday that the prospects for such a dialogue had been dampened by the brutal crackdown in the wake of the nation's disputed presidential election.

At a White House news conference with the German chancellor, Angela Merkel, Mr. Obama intensified his reproach of Iran's government and called for an end to deadly attacks against its people. He also engaged in an unusual exchange with President Mahmoud Ahmadinejad, brushing aside a suggestion that he apologize for criticizing Iran.

"I would suggest that Mr. Ahmadinejad think carefully about the obligations he owes to his own people," Mr. Obama said. "And he might want to consider looking at the families of those who've been beaten or shot or detained."

With Ms. Merkel at his side, Mr. Obama delivered some of his most pointed remarks against Iran since the violent protests began two weeks ago. Ms. Merkel said Germany and other nations shared his view, saying, "Iran cannot count on the world turning a blind eye."