BAGHDAD, Iraq — Representatives of Iraq’s main Shiite Muslim factions signed a deal yesterday clearing the way for Iraqi soldiers to operate throughout Sadr City, a vast Baghdad slum that is largely under the control of militiamen loyal to firebrand cleric Muqtada al-Sadr.

The signatures put an official seal to a truce that was brokered over the weekend by Mr. Sadr’s political representatives and members of Prime Minister al-Maliki’s governing alliance.

Negotiators said they hoped the deal would mark the close of more than seven weeks of fighting in the district, which has claimed hundreds of lives. But it remained to be seen whether all the groups that have taken up arms in Sadr City would adhere to the accord.

The American military said its troops in the southeastern portion of the district had come under attack at least three times since the deal began to take effect on Sunday and had killed three gunmen. Iraqi soldiers had also traded sporadic fire with neighborhood fighters, residents said. The district’s two main hospitals had received four bodies and treated 24 wounded since late Sunday, officials said.

Some militiamen said they were waiting for orders from Mr. Sadr himself before setting aside their weapons. But Mr. Sadr chief negotiator, Sheik Salah Obeidi, said yesterday the cleric had issued written instructions authorizing his representatives to sign the deal and urging his followers to uphold it.

The fighting erupted in late March when Mr. Maliki’s government began a crackdown in the southern oil hub of Basra aimed primarily at Mr. Sadr’s Mahdi Army militia.