"More than 100 settlements and organizations observe the ceasefire regime. With regard to potential renewal of ceasefire regime in Aleppo, the point is how the Nusra Front and the organizations affiliated with it will behave," Ryabkov told reporters.
Moscow continues urging Washington to make a distinction between such groups and entities, but these attempts have not been successful so far, he added.
Syria has been mired in civil war since 2011, with government forces loyal to Syrian President Bashar Assad fighting numerous opposition factions and extremist groups.
A US-Russia-brokered ceasefire came into force across Syria on February 27, but it does not apply to terrorist organizations active in the country, such as Nusra Front, which is outlawed in many countries, including Russia. Despite the ceasefire agreement, violence has escalated in Syria in recent weeks, especially in the northern Aleppo region.
