A senior Iraqi official has accused an Iraq-based Iranian opposition group of planning a homicide attack against Iraqi security forces, raising concern that the government in Baghdad may try to expel the exiles from the country.

The Iraqi government has promised not to forcibly evict the People's Mujahedeen Organization of Iran from its Camp Ashraf base north of Baghdad.

But National Security Adviser Mouwaffak al-Rubaie was quoted as saying that a camp resident confessed that his leaders told him to carry out an attack against Iraqi security forces guarding Ashraf.

The People's Mujahedeen, known as the Mujahedeen Khalq, denied the allegation as a "sheer lie."

Iraq is under pressure from neighboring Iran to deport the group. Although the U.S. has branded People's Mujahedeen a terrorist organization, Washington does not want its members deported to Iran.

Iraq assumed responsibility for Camp Ashraf from the U.S. on Jan. 1 under a new security agreement. The U.S. said it would maintain a presence at the base.

Al-Rubaie made his allegation Monday in Iran. He said the goal of the alleged plot was to embarrass the Iraqi government and generate international sympathy for the exiles, the state-owned Al-Sabah newspaper reported Tuesday.

The suspect who purportedly confessed was given immunity and protection by the Iraqi government, which promised to help him emigrate to a third country, the newspaper quoted al-Rubaie as saying.

Al-Rubaie could not be reached for comment, but an official in his office confirmed the remarks.

The official, who spoke on condition of anonymity because he wasn't authorized to release the information, also said the government has given the 3,500 members of the People's Mujahedeen two months to find another country.

The People's Mujahedeen was founded in Iran in the 1960s and helped followers of Ayatollah Ruhollah Khomeini overthrow U.S.-backed Shah Mohammed Reza Pahlavi in 1979.

But the People's Mujahedeen fell out with Khomeini, and thousands of its followers were killed, imprisoned or forced into exile.

Camp Ashraf was established in 1986 when Saddam Hussein allowed the People's Mujahedeen to establish a base north of Baghdad to launch raids into Iran.

The People's Mujahedeen was added to the U.S. terrorist list in 1997. The group insists the designation is unfair, saying it renounced violence in 2001 and kept arms only to defend itself.

After U.S.-led forces overthrew Saddam in 2003, American troops removed the group's weapons and confined its fighters to the camp.

Prime Minister Nouri al-Maliki, a Shiite, said this month that the People's Mujahedeen can "no longer operate in Iraq" but pledged he would not force the group back to Iran. U.S. Ambassador Ryan Crocker has said that the Iraqi government had given similar assurances to U.S. authorities.

On Wednesday, government spokesman Ali al-Dabbagh could not immediately be reached for comment on whether the policy had changed.