"Turkey is trying to handle the Nusra matter in Syria's north, and they [the Turks] want to make this group a political group, like Hezbollah in Lebanon", the source said.
The Turkish government hasn't yet confirmed the information.
The source in the Syrian Negotiation Commission (SNC) has also stated that Turkey wants to involve the Nusra Front terrorist group* in a new army in the north of Syria, where Ankara wants to set up a safe zone.
"Under the Turkish plan, Nusra will be involved in the national army in the north, which Turkey is trying to build now", the source said.
According to the source, the National Coalition for Syrian Revolutionary and Opposition Forces, which unites various opposition forces, and the SNC were both "working to enhance the Turkish agenda in the north — to create a safe zone 32 kilometres [19.8 miles] deep, taking the territory of 460 square kilometres [178 square miles]".
"There are meetings between the Coalition and Nusra Front to agree upon arrangements for the merger and formation of a new army in the Syrian north", the source stressed.
The source has also commented on the United States' stance regarding the plan.
"The US said we have no problem with any Turkish project in Syria's north as long it takes our allies' [the Kurds'] interests into account", the source said.
The statement comes after Russian Foreign Ministry spokeswoman Maria Zakharova pointed out last week that Nusra militants were building up forces in Idlib in the north of Syria, where Russia and Turkey agreed to set up a demilitarised zone along the contact line between Syrian government forces and the armed opposition. The zone was supposed to have no heavy weaponry or extremist fighters. Russia has warned that the presence of Nusra militants in Idlib violates the agreements on the zone.
In January US counterpart Donald Trump in a conversation with Erdogan had proposed establishing a 30-kilometre buffer zone in Syria. According to Erdogan, the future security zone will be controlled by the Turkish military.
*Al-Nusra Front or Jabhat al-Nusra, known as Jabhat Fatah al-Sham is a terrorist group banned in Russia