Under a heavy police presence, Salwan Momika, a 37-year-old who fled to Sweden several years ago, on Wednesday stomped on the Koran before setting several pages alight in front of Stockholm's largest mosque.

Police had granted him a permit for the protest in line with free-speech protections, but said later it had opened an investigation into the Koran burning which sparked anger across the Muslim world.

The incident occurred as Muslims around the world marked the Eid al-Adha holiday.

The Iraqi government in a statement issued late Wednesday strongly condemned "the repeated acts of burning copies of the holy Koran by individuals with extremist and disturbed minds".

"These acts demonstrate a hateful and aggressive spirit that goes against the principles of freedom of expression," it said.

"They are not only racist but also promote violence and hatred.

"These irresponsible actions, in direct conflict with the values of respect for diversity and the beliefs of others, are unequivocally condemned."

Morocco also condemned the Koran burning and recalled its ambassador to Stockholm late Wednesday.

"This new offensive and irresponsible act disregards the feelings of more than a billion Muslims, at this sacred time of the great pilgrimage to Mecca and the blessed feast of Eid al-Adha," it said in a statement.

"Faced with these repeated provocations, committed under the complacent gaze of the Swedish government", Morocco summoned Sweden's charge d'affaires in Rabat and recalled its ambassador, it added.

In January, a Swedish-Danish right-wing extremist burned a copy of the Koran near the Turkish embassy in Stockholm, also triggering outrage in the Muslim world.