Baghdad - The Sadrist bloc in Iraq's parliament refused a presidential invitation for a meeting to be held on Friday to discuss the US-Iraqi security pact, the bloc's spokesman said.

The bloc loyal to Shiite cleric Muqtada al-Sadr, which holds 30 of 275 seats in the parliament, opposes the agreement and has demanded a timeline for US troops' withdrawal. Movement loyalists have taken to the street several times to protest the deal.

"The Sadrist bloc insists on refusing to attend the meetings, after its participation has been suspended before," Ahmed al-Massoudy told the Voices of Iraq (VOI) news agency on Thursday.

Al-Massoudy said the pact aims at "legitimizing the presence of the occupation troops" adding that his bloc insists on the US troops' withdrawal from Iraq "as there is no reason for their presence."

The Iraqi political leadership demanded several months ago that all blocs dissolve their militias to be able to participate in political life. The Sadrist bloc regarded this call as a way to marginalize the group.

Members of the Mahdi Army, the military wing of the Sadrist bloc, were involved in fierce battles with US forces in April and August 2004. There were also relentless clashes between government forces and the Mahdi militiamen, described in a Pentagon report in 2006 as the greatest threat to the country's security, even greater than the al-Qaeda terrorist network.

Last August, al-Sadr ordered an indefinite halt to the armed operations, while creating a "cultural programme" to increase awareness for the Mahdi Army.

Al-Sadr has previously pledged his "political and popular support" for the Iraqi government provided it avoids endorsing a long-term security agreement with the US.

The security pact, known as the Status of Forces Agreement (SOFA), would lay down the legal basis for a continued US military presence in Iraq after a UN mandate expires in December. The Pentagon said Thursday that negotiators had reached a tentative agreement, which still must be approved by lawmakers in both countries.

A number of Iraqi politicians and lawmakers are against the mandate, saying it will violate the country's sovereignty. (dpa)