China has warned of "terrorist organisations" including remnants of Daesh* rising again in Syria if the international community ignores the "early warning" signs.
Xie Xiaoyan, Beijing's envoy in Syrian, said: "There is now a danger of terrorist organisations like ISIS (Daesh) being revived. The international community should pay attention."
He was meeting in Geneva with the United Nations Special Envoy for Syria, Geir Pedersen.
After the so-called Arab Spring, rebels challenged the government of President Assad in 2011 and three years later Daesh, an extremist Sunni Muslim militia, overran a huge chunk of eastern Syria and northern Iraq and proclaimed a “caliphate.”
Eventually Daesh was forced to retreat and in March this year it relinquished its last stronghold, Baghouz, to the Kurdish-led Syrian Democratic Forces’ (SDF).
The focus has now turned to Idlib, which since January has been administered by the Hayat Tahrir al-Sham alliance, led by jihadists from Syria's former Al-Qaeda affiliate.
The UN has warned President Assad and his Russian allies an assault on Idlib could trigger a humanitarian catastrophe.
Tens of thousands of Daesh fighters who fled the region around Raqqa last year are believed to have infiltrated Idlib and are preparing for a last stand against the Syrian Army.
Mr Xie said the situation in Idlib was "very complicated".
He said: "We all know that this is the last stronghold of some of the terrorist organisations... so this is an issue that needs to be dealt with. The fight against terrorism is not finished yet."
*Daesh, also known as ISIS, ISIL, IS is a terrorist group, banned in many countries, including Russia.