In the wake of this week's riots across England, the Iranian Foreign Ministry issued a statement on its Web site Thursday warning its citizens against visiting the UK, adding they should avoid troubled areas if they must make the trip.

Iran also advised its citizens in England to be on high alert, after calling on the British government to exercise restraint in handling the riots.

President Mahmoud Ahmadinejad called on the United Nations Security Council to step in and investigate the recent unrest gripping Britain, the English-language Tehran Times reported Thursday.

"The people protesting the wrong policies (of the government) are being beaten on the streets of London. Such brutal actions are in no way acceptable, and the officials of the country should listen to the voice of their people and allow them to participate in the major affairs of the country," he said.

He added that this was a "litmus test" for the U.N. to show whether or not it can play a role in the management of the world's affairs.

Ahmadinejad's comments came after London rapped Tehran for curtailing press freedoms.

In a letter to Iran's Foreign Ministry, Britain's top diplomat in Tehran urged Iran to allow a U.N.-appointed investigator looking into alleged human rights violations in Iran to enter the country.

Britain told Iran it would be more than willing to discuss its handling of street unrest, after Ahmadinejad accused UK police of "savage aggression" against demonstrators.

British Prime Minister David Cameron said on Wednesday:

"I will not allow a culture of fear to exist on our streets."

However, Ahmadinejad said in a statement published by state-funded broadcaster Press TV:

"The true opposition in Britain is the people that are pushed to the ground and beaten on London streets and slain, and yet no one hears their voice."

Iran was lambasted by the international community for its crackdown on opposition protesters taking part in the so-called Green Revolution after the controversial elections in 2009. Eight people were killed in protests against Ahmadinejad's disputed re-election.

The unrest in the UK began Saturday in the north London suburb of Tottenham after several hundred people gathered outside a police station to protest the fatal shooting of Mark Duggan. The riots, which had gripped northern London, spread midweek with arson, looting and violence in other English cities.