BAGHDAD, Iraq, June 5 — Fighters loyal to Moktada al-Sadr, the Shiite radical who fashioned an army from the discontented of Iraq's slums, began to withdraw Saturday from the centers of Najaf and Kufa, where they have been battling American forces since April.

At the same time, Mr. Sadr met with Grand Ayatollah Ali al-Sistani, Iraq's most revered Shiite cleric, according to widespread reports. The meeting suggested that Mr. Sadr was being given a face-saving gesture by appearing with Ayatollah Sistani, whose prestige across Iraq far exceeds that of Mr. Sadr.

Shiite leaders and American officials said the armed followers of Mr. Sadr, known as the Mahdi Army, had cleared out of many parts of Najaf, and seemed to be getting ready to leave altogether. The Shiite leaders said American forces, who encircled the city in recent weeks, had also cleared out of the city center and areas near the Imam Ali Shrine, one of the holiest sites in Shiite Islam.

The withdrawal, coupled with the reported meeting of the rival clerics, gave rise to hopes that Mr. Sadr's two-month-long rebellion may be ending...