The 10-kilometre (six mile) deep quake hit 27 kilometres northwest of the port city of Genaveh at 11:11 am local time (0641 GMT) and was felt in nearby provinces, Iran's seismological agency said.

State news agency IRNA reported that the quake and several aftershocks caused power blackouts and cut phone lines nearby but caused "no damage" at the Bushehr nuclear complex about 100 kilometres away.

"The minor damage to Genaveh's water, electricity, telecommunication and gas infrastructure has been repaired," the head of the province's crisis management told IRNA.

Iran sits astride the boundaries of several major tectonic plates and experiences frequent seismic activity.

In 2003, a 6.6-magnitude quake in southeastern Iran levelled the ancient mud-brick city of Bam and killed at least 31,000 people.

Iran's deadliest quake was a 7.4-magnitude tremor in 1990 that killed 40,000 people in the north, injured 300,000 and left half a million homeless.