Sadr spokesman Salah al-Obeidi said a statement released Tuesday by the cleric calling for weekly protests against the series of security deals extending the U.S. presence in Iraq beyond 2008 was a warning to the government, not a threat, Al-Alam said.
"(Sadr) warns that only the government must take responsibility for such a decision," Obeidi said.
The spokesman also said Sadr urged all political parties and the people of Iraq "to adopt a unified stance toward the future Iraqi government and how to contribute to it."
Any future relationship with the United States could, however, be made through a vote in the Iraqi Parliament, Obeidi said.
There has been no official word on the issue from Iraqi religious leader Grand Ayatollah Ali al-Sistani, but his aides said the revered cleric supports discussing the matter in a public forum.
"If the majority of the people accept it, then they should go ahead," an aide said.