Iran said they are outraged over the Obama administration's allegations of complicity in a plot to assassinate Saudi Arabia's ambassador to the U.S.

On Wednesday, Attorney General Eric Holder announced that the U.S. had thwarted an Iranian plan to bomb the Saudi and Israeli embassies in Washington and assassinate Saudi Ambassador Adel al-Jubeir on American soil.

Iran "strongly and categorically" denied any involvement in the plot.

In a letter to U.N. Secretary-General Ban Ki-moon, Iranian Ambassador Mohammad Khazaee expressed "outrage" at U.S. allegations, Iran's state-run FARS news agency reported.

"I am writing to you to express our outrage regarding the allegations leveled by the United States officials against the Islamic Republic of Iran on the involvement of my country in an assassination plot targeting a foreign diplomat in Washington," the ambassador wrote.

He called the allegation "politically motivated."

"The Islamic Republic of Iran categorically and in the strongest terms condemns this shameful allegation by the United States authorities and deplores it as a well-thought evil plot in line with their anti-Iranian policy to divert attention from the current economic and social problems at home and the popular revolutions and protests against United States long supported dictatorial regimes abroad," Khazaee wrote.  

"The Iranian nation seeks a world free from terrorism and considers the current U.S. warmongering and propaganda machine against Iran as a threat not just against itself but to the peace and stability in the Persian Gulf region," he said.