Iran has eased conditions for opposition leader Mehdi Karroubi, who has been under house arrest since 2011, allowing him to receive visitors, one of his sons said on Monday.

Mohammed Hossein Karroubi was speaking to ISNA and ILNA news agencies, which are close to the Iranian reformist camp.

"Since his release from hospital (in mid-August), members of his family, his children, his daughters-in-law and his grandchildren have been able to see him... at any time and without any problem," he said.

Karroubi, who turned 80 in September, has also been allowed to receive political figures at home, after their names were cleared by the authorities, his son added.

Ismail Dousti, of the Etemad Melli (National Confidence) party founded by Karroubi, was able to meet the opposition leader twice in September and October, the Karroubi family said.

Karroubi and opposition leader Mir Hossein Mousavi -- both former presidential candidates -- have been in detention since February 2011 for their role in anti-government protests.

The protests followed allegations of rigging in the 2009 presidential election which they lost to hardliner Mahmoud Ahmadinejad.

Neither has ever been charged with a crime.

President Hassan Rouhani has repeatedly said he would work for the release of Mousavi and Karroubi, and thousands chanted their names at rallies in May during his campaign for re-election.

Karroubi underwent heart surgery in August after going on a brief hunger strike to demand a trial and the removal of intelligence agents who were posted inside his home.

After his release from hospital his demand was granted and the agents were posted outside the house.

Meanwhile, Mousavi was on Friday authorised to see his two sisters, according to Iranian media reports.

At the end of October, a senior official told reporters that the term "house arrest" referring to Karroubi and Mousavi was "inappropriate".

"Karroubi asked to see Mr Dousti and he was able to do so... They can meet anyone they wish," said Ali Shamkhani, secretary of the Supreme National Security Council.

Source: AFP