An Iranian security court has begun the closed-door espionage trial of an Iranian-US reporter for The Washington Post who has been detained for more than 10 months.

Jason Rezaian, the Post's 39-year-old bureau chief in Teheran, is being tried in a Revolutionary Court.

He is accused of "espionage for the hostile government of the United States" and propaganda against the Islamic republic, Iran's official IRNA news agency said without elaborating.