Talks to end bitter fighting between U.S. forces and Shiite militants in the Baghdad slum of Sadr City have stalled, with the government refusing militant demands for American troops to keep out of the troubled district, officials said Wednesday. Naim al-Kaabi, a spokesman for rebel Shiite cleric Muqtada al-Sadr, said a tentative agreement was initially reached Monday with government negotiators on a six-point proposal that would have barred American troops from entering Sadr City without Iraqi government permission. But on Tuesday, government negotiators backpedaled, expressing concern that such a deal would incite residents of other Baghdad neighborhoods or Iraqi cities to also call for restrictions on the movement of U.S. troops, al-Kaabi said. A senior Iraqi government official refused to comment when asked about the issue and other government officials were unavailable for comment. Maj. Phil Smith, an Army spokesman for the Baghdad-based 1st Cavalry Division, said U.S. commanders were not involved in any talks and that as far as he was aware, "no agreement has been reached." Al-Kaabi said that al-Sadr representatives were willing to hold further talks to reach an accord and had issued a proposal that would allow U.S. troops to enter Sadr City without government approval only if they were going there to carry out reconstruction work. He said he hoped to receive an answer from the government later Wednesday.