Iran condemned the planned removal of the Iranian dissident group Mujahadin-e Khalq (MEK) from the United States' list of terrorist organizations, Iranian media reported on Wednesday.
US officials said last week that Secretary of State Hillary Clinton had made the decision to remove MEK from the list, handing a political victory to a group once sheltered by Iraqi leader, and arch-foe of Iran, Saddam Hussein.
The group, also known as the People's Mujahideen Organization of Iran, calls for the overthrow of Iran's clerical leaders and fought alongside Saddam's forces in the Iran-Iraq war in the 1980s. It also led a guerrilla campaign against the US-backed Shah of Iran during the 1970s, including attacks on American targets.
"By taking this step the government of America must be held accountable for the blood of thousands of Iranians and Iraqis assassinated by members of this sectarian group," said Ramin Mehmanparast, spokesman for the Iranian foreign ministry, the Mehr news agency reported on Wednesday.
The US decision comes after years of intense lobbying by the MEK, which had seen many of its members stranded in Iraq even as the group fell out of Baghdad's favor after Saddam's downfall.
The United States added the MEK to its list of foreign terrorist organizations in 1997. But the group has since said it renounced violence and mounted a vigorous legal and public relations campaign to have the designation dropped, including endorsements by prominent former US public officials.
The United States had repeatedly said its decision on the MEK's terrorist designation hinged partly on the group's remaining members leaving Camp Ashraf, an Iraqi base where they had lived for decades, and moving to a former US military base in Baghdad from which they were expected to be resettled overseas.
Officials said last week that the final large group of dissidents had moved from Camp Ashraf to the new location, ending a long standoff with Iraqi authorities.
"The moving of the members of this terrorist group from Camp Ashraf to another place is not at all an acceptable excuse … for the terrorist nature of this group to be ignored," Mehmanparast said, according to Mehr.
"If America removes this group, with a long history of terrorist actions, from its list, it would be a breach of its international obligations and undermine global efforts to combat terrorism."