Iran has called on the British government to "restrain" the police and stop the "violent treatment" of rioters.

The foreign ministry spokesman, Ramin Mehmanparast, said dialogue would calm the situation, and urged the UK to respond to the demands of the "protesters". He also asked human rights organisations to investigate the death of Mark Duggan, which led to the riots.

As diplomatic tension continues between the two countries, officials in Tehran seized on the unrest as an opportunity to repay the British government for its criticism of human rights violations in Iran.

Human rights groups say dozens of activists were killed and thousands detained after Iran's disputed presidential elections in 2009, and there are widespread allegations of torture and rape inside the country's prisons.

This year Tehran was infuriated by British support for the appointment of a UN special rapporteur to investigate abuses.

A prominent conservative MP said Iran was ready to dispatch a group of experts to investigate "human rights violations" in the UK.

Hossein Ebrahimi, the deputy head of the parliamentary committee on national security and foreign policy, said Britain should facilitate the visit "without making false excuses", according to the English-language state-run Press TV.

"Ebrahimi said that the group of rapporteurs intend to interview political detainees and to give a report to international bodies on the treatment received by the protesters," the report said.

Iranian media sympathetic to the regime have portrayed the recent rioting and looting across London and other cities as social unrest fuelled by living conditions and police mistreatment of the poor.

Iranian MPs condemned what they described as police violence . "An Iranian majlis [parliament] national security and foreign policy subcommittee has urged the UK to immediately stop violent treatment of people protesting the killing of a black man," Press TV reported on Tuesday.

According to Press TV, Mohammad Karim Abedi, the vice-chairman of the parliamentary committee "urged London to order the police to stop treating protesters violently".

Iran's semi-official Fars news agency, which is affiliated to the elite revolutionary guards, has given extensive coverage to the rioting and looting across Britain. "We advise the monarchical regime of Britain to respect the rights of its people by avoiding savage behaviour," Fars quoted Seyed Hossein Naqavi, an Iranian MP of the parliamentary human rights committee, as saying.

According to Fars, Naqavi said: "The British people have come to the streets to protest at the security forces' deliberate gunfire at Duggan."

Press TV said Naqavi had also condemned what he called the UK's "double standards towards human rights".

Iranian opposition and reformist newspapers have distanced themselves from the official reaction to the UK riots.