Iran's president has denied U.S. allegations that Iran was involved in a plot to kill the Saudi ambassador in the U.S.

Mahmoud Ahmadinejad said Sunday Iranians are civilized and do not need to resort to assassination.

The highest-ranking U.S. Senator on intelligence matters, Diane Feinstein, told Fox News Sunday that U.S. authorities have collected ample evidence showing the involvement of Iran's elite Quds force in the plot.

She added there is “no question” that the Quds force is responsible for plotting several violent terrorist operations.

Iran's Supreme Leader Ayatollah Ali Khamenei said Saturday U.S. claims that Tehran supported an alleged assassination plot are absurd. The supreme leader accused the U.S. of making “unfounded” accusations against “a few Iranians in America” as part of an effort to isolate Iran.

Last Tuesday, the U.S. Justice Department announced it had broken up an alleged Iranian plot to assassinate Saudi Ambassador to the U.S. Adel al-Jubeir. Officials said the U.S. had filed charges against two Iranians for involvement in the plot. Officials said one suspect was part of Iran's elite Quds Force.

On Friday, U.S. State Department spokeswoman Victoria Nuland said Washington had a direct meeting with Iranian officials over the alleged plot. She told reporters the meeting was to make it “absolutely clear” that the U.S. considers the alleged plot “unacceptable” and a violation of U.S. and international law.