The death toll in the 6.8 magnitude earthquake which struck eastern Turkey on Friday has risen to 18, while over 550 others have sustained injuries, country's Interior Minister Suleyman Soylu said on Saturday.

As many as 35 aftershocks have been registered since the initial quake, varying from 2.7 to 5.4 magnitude, Anadolu Agency reported, citing the country's Disaster and Emergency Management Agency.

Several Turkish humanitarian organisations have despatched their rescue teams, providing food, blankets, and other necessities to those affected by the quake.

The epicentre of the initial quake, which occurred at 5:55 pm (UTC), was registered at a depth of 15 kilometres, about 218 kilometres northeast of the city of Gaziantep, according to the European-Mediterranean Seismological Centre.

Meanwhile, Turkish President Recep Tayyip Erdogan has said that all relevant departments have taken measures to ensure the safety of the citizens.

Greek Foreign Minister Nikos Dendias had earlier held a telephonic conversation with Turkish counterpart Mevlut Cavusoglu and offered his country's assistance.