World News : U.S. says Tehran denial about contacts not truthful

WASHINGTON (World News) - The United States held rare direct contacts with Iran over allegations that Tehran was behind an alleged plot to kill the Saudi ambassador on U.S. soil, the State Department said on Friday, dismissing Iranian denials that any meeting had taken place.

"I will again confirm that we did meet with the Iranians," State Department spokeswoman Victoria Nuland said.

"They know that very well, and any efforts on their part to deny it speaks again to how truthful they are about any of these sorts of matters," she added.

Nuland had initially indicated the meeting took place on Wednesday but U.S. officials later clarified it was on Tuesday. The spokeswoman declined to identify the participants or the venue of the meeting.

U.S. authorities said on Tuesday they had broken up a plot by two men linked to Iran's security agencies to kill Saudi Ambassador Adel al-Jubeir in Washington. One was arrested last month while the other was believed to be in Iran.

"The substance on our side was to make absolutely clear that we consider this whole behavior a violation of U.S. law, a violation of international law and unacceptable and that we intend to hold them to account," Nuland said.

President Barack Obama warned Iran it would face the toughest possible sanctions over the alleged plot.

Earlier on Friday, Iran's semi-official Mehr news agency reported that an official at Iran's U.N. mission denied that Tehran had been in direct contact with the United States over the assassination plot allegations.

"There has been no direct contact between the two countries," Alireza Miryousefi, an official in charge of the media at Iran's U.N. mission, told Mehr.

Iran called the accusations a fabrication designed to stoke tensions in its relations with its neighbors, already under strain over its nuclear program.

Iran and the United States are at loggerheads over Tehran's disputed nuclear program, which Washington and its allies fear is aimed at making a nuclear bomb.

Tehran denies this, saying it only wants to generate electricity. The plot allegation raises tensions to a new level between the Obama administration and Iran.