Iranian dissident and cleric Ali Tehrani, brother-in-law of supreme leader Ali Khamenei, has died in Tehran aged 96, news agency ISNA said Thursday.

Born Ali Moradkhani, Sheikh Tehrani married Khamenei's sister Badri in 1962.

He lived in exile in Baghdad in neighbouring Iraq from 1984 to 1995, where he strongly criticised the Islamic republic in radio broadcasts.

Badri fled to Baghdad to join her husband at the peak of the 1980-1988 Iran-Iraq war.

In a memoir published on his official website, Tehrani praised his wife for "always staying by my side, before and after the Islamic revolution".

He had a short-lived career at the judiciary authority immediately after the establishment of the Islamic republic, before being elected to an assembly that was charged with drafting its constitution.

A critic of the Islamic republic, Tehrani also opposed the monarchy led by US-backed shah Mohammed Reza Pahlavi, who was toppled in the revolution of 1979.

Tehrani had been imprisoned by the shah's secret service over his support for the revolutionary leader Ayatollah Ruhollah Khomeini.

After his return from exile in 1995, Tehrani was sentenced to 20 years in jail, out of which he served seven years "in different prisons", according to his memoir.

He renewed his opposition to the Islamic republic in a statement on February 10, 2021, marking the anniversary of the 1979 revolution.

"In the first referendum after the revolution, we should have put the Iranian republic to the vote -- not the Islamic republic -- because the conditions today are different from those in the times of the prophet of Islam," he said.

Tehrani is survived by his wife, who lived with him in Tehran.

Their daughter, Farideh Moradkhani, has gained prominence as an anti-death penalty activist.

She was arrested in January, months after she took part in a celebration praising the widow of the ousted shah.

Their oldest son, Mahmoud, also an opponent of the Islamic republic, lives in France.