BAGHDAD (AFP) -- Iraq's radical Shiite cleric Moqtada Sadr called on the government not to sign an accord being negotiated with Washington that will govern the presence of U.S. troops from next year.

The security agreement have been sealed in principle by Thursday to take over from a UN mandate which expires this December, but Washington has said that date was unlikely to be met.
A U.S. embassy official on Thursday confirmed to AFP that the negotiations were ongoing, describing them as ""constructive.""
""I call on the Iraqi government not to sign the accord with the United States and I affirm that I am ready to support the government publicly and politically if it does not sign,"" Sadr said in a statement.
The influential Shiite leader called on ""men of faith and on the clergy to express legally their opinion against the signature of any agreement between the government and the occupier, even if it is a friendly accord or one concerning another subject.""
Sadr, who strongly opposes the American troop presence which he sees as an occupying force, called on Iraqis ""to be united to stand up against this agreement by political, peaceful and public means.""
The Mahdi Army, the armed wing of Sadr's movement, clashed in April and May with U.S. and Iraqi troops in the Shiite bastion of Sadr City in Baghdad, until a truce was signed on May 10.
The United States has about 142,500 troops stationed in Iraq where Prime Minister Nuri al-Maliki this month shook the White House by saying he was in favor of setting a date for the withdrawal of U.S. combat troops.
U.S. President George W. Bush has repeatedly refused to give a time-table for the overall withdrawal of U.S. forces from Iraq.
But Iraqi leaders, including Maliki, are demanding such a timetable to be included as part of a security deal now being negotiated by the two countries for the future presence of U.S. forces in Iraq.
A U.S. embassy official in Baghdad told AFP earlier in July that the originally envisaged security pact called Status of Forces Agreement (SOFA) has now been ""suspended"".
""The SOFA as we had in Japan or Germany has been suspended or put aside but not thrown away.""
He said the two sides were negotiating a ""security protocol or operational protocol"" that contains the key contents of the SOFA but would be only for a ""certain period of time.""