Syria’s new leadership has taken steps to unite disparate rebel factions under a single government in the wake of Bashar al-Assad’s ouster.

Under a new accord, a number of rebel factions agreed to dissolve themselves, Sana, the Syrian state-run news service, reported on Tuesday. The agreement suggested that the new Syrian administration was making progress in asserting its authority over the country.

The rebel groups agreed to be integrated under the defense ministry, the Sana report said. Pictures posted on social media showed Ahmad al-Shara, the rebel who led the offensive that overthrew the Assad dictatorship, meeting on Tuesday with dozens of rebels, many of them clad in military uniforms.

On Sunday, Mr. al-Shara, who has sought to present himself as a moderate despite past links to Islamist extremists, told a news conference that the “logic of a state is different from the logic of a revolution.” He spoke standing alongside Turkey’s foreign minister, Hakan Fidan.

“We absolutely will not allow for weapons outside the framework of the state,” Mr. al-Shara said.

That mandate covers a range of rebel factions and a separate Kurdish-led militia, the Syrian Democratic Forces, which controls northeastern Syria and is backed by the U.S. military.

It was not immediately clear whether all rebel factions had signed onto the new unity agreement, and the Syrian Democratic Forces did not appear to be part of the deal.

The Kurdish-led force has been battling the Islamic State terrorist group for years inside Syria. Neighboring Turkey is hostile to the Kurdish force, viewing it as an extension of a Kurdish group in Turkey that has been fighting the Turkish state for decades.

Muhammad Haj Kadour contributed reporting.