Despite repeated denials of Iran's involvement in a recent plot to assassinate the Saudi ambassador in Washington, the Iranian foreign minister admitted his country's involvement on Wednesday, Al Arabiya news reported.

An Iranian source told the Saudi-owned news agency that Foreign Minister Ali Akbar Salehi recently met with Mohammed Nahavandian, former assistant at the National Security Council and the current president of the Chamber of Commerce and Industry. In the meeting, Salehi allegedly disclosed the involvement of Iran's Revolutionary Guard's Quds Force in the plot.

"This is true. The plot was about to be carried out. It is not a figment of the American authorities' imagination," the source quoted Salehi as saying.

The source is close to Gholam Hussein Elham, former spokesman of the Iranian government and a current dissident of the regime in Tehran.

Manssor Arbabsiar, an Iranian-American car salesman living in Texas, and Gholam Shakuri, accused of being an Iran-based member of the Revolutionary Guard Quds Force, were indicted for their involvement in the plot in the U.S. District Court in Manhattan Oct. 20. Arbabsiar pleaded not guilty to the charges last week.

For its part, the Iranian government insists the plot is an American fabrication and has even demanded an apology from the United States for its accusations against Iran.

"Instead of pursuing this scenario and the wrong path of foreign policy in which they are moving, Americans had better move to correct this path," Iran's official news agency IRNA reported that foreign ministry spokesman Ramin Mehmanparast said. "A letter has been sent [to the United States] ... It is our right to seek the official apology of the Americans in protest of this made-up scenario, as these allegations are not true at all," he added.

The United States on Tuesday dismissed the Iranian letter as "a rant" and Saudi Arabia has ruled out the possibility of negotiating with Iran about the plot.

"There can be no compromise with Iran concerning the assassination bid because there is no need for it," the Crown Prince Naif bin Abdulaziz, who is also the deputy premier and interior minister, told a news conference on Tuesday. "We are ready to deal with any scenario... with any means necessary."