Iran has charged two French nationals and a Belgian national with espionage and activities against the country's national security, the semi-official Student News Network reported, quoting a judiciary spokesman. 

Names of these three people were not released, and no details were given about where and when the charges were filed. Belgium's justice minister said last month that a Belgian aid worker, Olivier Vandecasteele, had been sentenced to 28 years in prison in Iran, based on what he called "a series of trumped-up offences". 

In October, Iranian media broadcast a video in which two French nationals appeared to confess to spying during a period of unrest that Tehran blamed on external enemies. 

French foreign minister said in November that seven French citizens were being held in Iran, a sign of further deterioration in relations between the two countries. 

The Islamic Republic has blamed foreign enemies for fueling a wave of unrest that began three months ago after the death of 22-year-old Iranian-Kurdish Mahsa Amini while being held in custody by morality police for violating mandatory dress codes. 

The protests marked one of the boldest challenges to the Iranian leadership since the Islamic Revolution of 1979. The protests were joined by Iranians from all walks of life, the VOA reported.