"This has not been proposed by any member state… In none of our meetings was this issue raised by any of the member states," Mogherini told reporters ahead of the Foreign Affairs Council.
She said "there are discussions for sure" pertaining to existing measures against the Syrian government, adding "that could be possible."
"The European Union doesn't only have sanctions in its toolbox… We have the instruments for pressure, we also have leverages for good. And so a good mix of the two is always wise and useful, so today we will focus on all tracks," Mogherini stressed.
Russia has been mediating talks on Syria in search of a political solution to the conflict, as well as assisting Damascus in fighting extremists. Moscow's counterterrorist air campaign in Syria was launched on September 30, 2015, at the request of Assad. Separately, a US-led coalition of some 60 states has been conducting airstrikes on terrorists in Syria, without either UN mandate or Damascus' approval.