Saudi envoy murder plot suspect pleads not guilty

Manssor Arbabsiar is shown in this courtroom sketch during an appearance in a Manhattan courtroom in New York, New York on October 11, 2011.

NEW YORK (Reuters) - An Iranian-American man who U.S. officials say has links to Iran's security forces pleaded not guilty in federal court on Monday to plotting to kill the Saudi ambassador to Washington in a bomb attack.

Manssor Arbabsiar, 56, who was arrested on September 29 in New York, faces several charges including conspiracy to murder a foreign official, conspiracy to use a weapon of mass destruction and conspiracy to commit an act of terrorism.

Another man, Gholam Shakuri, also was charged in the plot but is believed to still be in Iran. U.S. officials said he is a member of Iran's Quds Force, the covert operations arm of the country's powerful Islamic Revolutionary Guard Corps.

Arbabsiar will be back in Manhattan federal court on December 21 for a status update hearing.

U.S. prosecutors accused the two men of planning to assassinate the Saudi ambassador to the United States, Adel al-Jubeir, by planting a bomb in a Washington restaurant. The Iranian government denies any involvement.

But details such as Arbabsiar's bumbling nature and his trust of a U.S. federal informant impersonating a Mexican drug cartel figure, have raised questions among Iran specialists as to the seriousness of the plot.

The consensus view in President Barack Obama's administration is that Iran's supreme leader, Ayatollah Ali Khamanei, probably knew of the alleged plot while President Mahmoud Ahmadinejad did not.

Ahmadinejad has said Washington had fabricated the plot to cause a rift between Tehran and Saudi Arabia and dominate the oil-rich Gulf.

U.S. officials have said Arbabsiar has confessed to his role in the assassination plot.

During Monday's five-minute hearing, Judge John Keenan asked defense attorney Sabrina Shroff whether she planned to file court papers questioning whether Arbabsiar's alleged confession to authorities was made against his rights.

"Most certainly, your honor," Shroff said.

(Editing by Michelle Nichols and Bill Trott)