Syria's new leadership has appointed Murhaf Abu Qasra, a prominent figure in the insurgency that toppled President Bashar Al-Assad, as defense minister in the interim government, an official source confirmed on Saturday, according to Reuters . Abu Qasra, also known by his nom de guerre Abu Hassan 600, is a senior member of the Islamist Hayat Tahrir Al-Sham (HTS) group, which spearheaded the campaign that led to Assad’s ousting earlier this month. Qasra played a leading role in numerous military operations during Syria's revolution, the source said. Syria’s de facto leader, Ahmed al-Sharaa, discussed "the form of the military institution in the new Syria" during a meeting with armed factions on Saturday, according to the state news agency SANA . Photos published by SANA showed Abu Qasra seated next to Sharaa, who is also known by his nom de guerre Abu Mohammed al-Julani, during the meeting. HTS was once a part of Al-Nusra Front, which is Syria’s Al-Qaeda branch. HTS is labeled a terrorist organization by many Western governments. HTS later broke off from Al-Nusra Front and prioritized combatting Al-Qaeda as well as the Islamic State (ISIS), of which Julani was critical , describing its self-proclaimed caliphate in parts of Syria and Iraq as "illegitimate". Qasra’s appointment as defense minister came days after he announced that HTS would be "the first" to disband their armed wing and merge with the Syrian national forces. Related articles: IAF strikes three tanks belonging to Assad's army in Syria Syria's new government to take power March 1 Transitional president sets 4-5 year timeline for elections Assad's cousin who led deadly 2011 crackdown arrested "In any state, all military units must be integrated into this institution," said Qasra said in an interview with AFP . His appointment also comes one day after the US announced that it would no longer pursue a reward for the arrest of Sharaa.