"Second, we want to see the full implementation of the relevant Security Council resolutions, including the ones about arming and financing terrorists as indicated by the SC," he added.
Other points include expectation of "accelerating efforts against Security Council-listed terrorists in Syria, and whenever feasible, some type of coordination of those efforts."
De Mistura also emphasized the need to protect civilians in Syria, while fighting terrorists.
"It must not be in any moment a possibility of using any type of prohibited weapons or weapons of mass civilian casualties. It must be done in accordance of with international humanitarian law," he said.
"Last but not the least, the best guarantee against terrorism in Syria is an agreed political solution," de Mistura added.