Greek Prime Minister Kyriakos Mitsotakis said on Thursday that illegal migrants denied asylum by Greece should be returned to their country of origin and called on the European Union to provide a new list of “safe countries” to help speed up the return process, Reuters reported.

“We are looking forward to a new list of safe countries of origin so that our country can move faster in this direction,” Mitsotakis said on arrival at an EU leaders' summit in Brussels.

Migration is one of the issues on the leaders' agenda, along with Ukraine and defense.

Greece was on the front lines of the migration crisis in 2015-2016 when more than a million people crossed its territory by sea, seeking to move further north in Europe.

The flow of migrants has since decreased, but irregular migration to the EU remains a hot political topic across Europe.