A massive cyberattack has caused widespread disruption at gas stations across Iran, affecting fuel distribution facilities, authorities said on Tuesday.

No group has so far claimed responsibility for the attack, which has sent shock waves across the country amid fears of a fuel crisis.

Officials at Iran's oil ministry told state media that they were holding emergency meetings to fix the problem that has forced the closure of gas stations across the country, including in capital Tehran.

The cyberattack has targeted the software that supports a smart card payment for subsidized fuel, used widely in Iran.

The attack appears to be timed with the anniversary of the November 2019 violent protests in Iran over fuel price hikes, which claimed many lives.

Iran's Interior Minister Ahmed Wahedi, trying to allay public fears, said in a statement that there was "no plan to increase fuel prices" this time, asking people "not to worry".

He attributed the disruption of fuel distribution services to a "technical glitch", which he assured will be "fixed soon".

Mostafa Akhi, a spokesman for parliament's energy commission, also ruled out fuel price hikes, urging people not to rush to gas stations until the problem is solved.

Anadolu Agency spoke to people in the capital Tehran, who said many gas stations remained closed hours after the cyberattack was first reported on Tuesday.

- I have been waiting to refuel my car at a gas station in north Tehran, but we have been asked to wait until the problem is fixed - said Ali Zamani, a private taxi driver.

The disruption has caused long lines in front of gas stations in the capital city.

There have been a series of cyberattacks in recent years, targeting Iran's nuclear sites, petroleum facilities, railway stations and ports. Officials have mostly blamed arch-enemy Israel for the attacks.

Meanwhile, in a related development, the semi-government news agency ISNA put out a statement on Tuesday, saying its website was also targeted in a cyberattack.

It came after the news website had published a story about the disruption of fuel services.