At least 150 were injured, Iraqi officials said.
Two people have died in the city of Qasr-e Shirin, Iranian TV reported, citing the country's Emergency Services.
As this is a breaking story, more news will be updated as made available.
Bam in the country's southeastern province of Kerman witnessed a strong quake in December 2003 which killed 31,000 people.
It struck the mountainous area of Sulaimaniyah province at 9:18 pm (1818 GMT) at a depth of 33.9 kilometres (21 miles), the monitor said.
Israeli media said the quake was felt in many parts of Israel too.
An Iraqi meteorology official told Reuters that the strong natural disaster which hit parts of Iraq on Sunday, including the capital Baghdad, was measuring 6.5 magnitude. The region where the quake struck sits upon one of several major fault lines in Iran, and although that country sees quakes nearly daily, the most deadly one in recent history struck in 2003 - a 6.6 magnitude quake that left 26,000 dead.
The semi-official Iranian ILNA news agency reported that at least 14 provinces had been impacted by the natural disaster.
Some have spoken of having felt the tremor in Kuwait. In the town of Diyarbakir, residents also left their homes before returning.