Iran on Monday slammed a US pastor's burning of a Koran, calling it provocative and demanding US authorities take action to prevent any recurrence.
Iran's foreign ministry said in a statement carried by the official IRNA news agency that it "strongly condemns this ridiculous, insulting and provoking act by a so-called American priest in overt contempt of the holy Koran."
The condemnation was in reaction to a Saturday ceremony in which Florida pastor Terry Jones set fire to the Muslim holy book and a depiction of the prophet Mohammed to protest Iran's imprisonment of an Iranian Christian clergyman, Yousef Nadarkhani.
The act was broadcast online in a YouTube video that climaxed with Jones and a handful of followers repeating the US oath of allegiance as the Koran burned.
Jones, who rebuffed a US Defence Department request to desist out of fear for US troops' safety abroad, was behind a March 2011 burning of the Koran by his assistant that triggered violence in northern Afghanistan in which at least 12 people were killed.
Iran's foreign ministry said the latest burning was the result of "Islamophobia" in the West.
It said the world was "awaiting a quick, serious and frank response by the US government to this act so it is never repeated."
The ministry said the Koran burning "undoubtedly creates religious hatred and will provoke Muslim anger worldwide."
The act by Jones came as US and Iranian officials prepared for important talks on Tehran's nuclear programme that are to be held in Baghdad on May 23.
While Iran is expressing optimism over those talks, any failure could stoke tensions between the Islamic republic and the West and strengthen the possibility of military action by the United States or Israel.
Nadarkhani, the Christian evangelical pastor in prison in Iran, was arrested in 2009 and condemned to death for converting to Christianity when he was 19.
Iran's supreme court overturned the death sentence in July 2011 and a retrial took place in September 2011, but no verdict was made public.
Nadarkhani's lawyer, Mohammad Ali Dadkhah, who himself risks incarceration for defending the pastor and a dissident in another case, told AFP that his client "must be released," based on religious edicts from prominent Iranian clerics.
The lawyer declined to comment on the Koran burning protest for Nadarkhani in the United States.