(Reuters) - Two California men have been charged in a scheme to smuggle more than $3 million worth of military aircraft parts and other defense items to Iran, U.S. federal prosecutors said on Friday.

Zavik Zargarian, 52, and Vache Nayirian, 57, who live outside Los Angeles, were arrested on Wednesday on suspicion of violating the International Emergency Economic Powers Act and the Iranian Transactions and Sanctions Regulations, the U.S. Department of Justice said in a statement.

"The crimes charged in this indictment are very serious threats to our national security," Acting Assistant Attorney General for National Security Mary McCord said on Friday. "As a nation, it is vital that we protect our military technology and prevent it from getting into the hands of other countries without proper authorization."

The U.S. embargo on Iran bars the export of goods, technology and services to the country with few exceptions.

If convicted, Zargarian faces a maximum sentence of 115 years in federal prison and a $4,770,000 fine, while Nayirian faces a maximum sentence of 95 years in prison and a $3,770,000 fine, prosecutors said.

The men, who have both pleaded not guilty, are scheduled for trial in federal court beginning on Dec. 20. They are among five defendants named in an indictment unsealed on Wednesday, which included Iranian nationals Hanri Terminassian, 55, and Hormoz Nowrouz, 56, who are believed to be in Iran.

Zargarian's Glendale, California-based company, ZNC Engineering, was also named as a defendant.

During an undercover federal investigation, Terminassian originally contacted Zargarian from Iran and asked for help with obtaining military aircraft parts from U.S. suppliers, prosecutors said.

Zargarian then negotiated with an undercover Department of Homeland Security agent posing as a supplier, the prosecutors said. They said Terminassian eventually traveled to the United States and met with Zargarian to discuss purchasing parts, including items used in F-16 and F-18 fighter jets.

Nayirian is accused of conspiring with Zargarian and Terminassian to export thousands of rubber O-rings, which can be used in aircraft hydraulic systems and landing gear, to the Iranian Air Force, prosecutors said.

(Reporting by Laila Kearney; Editing by Tom Brown)