Over 15,000 people have died in total following a catastrophic earthquake in the Turkish-Syria border region.

Turkish state news agency Anadolu Agency, citing the country's disaster management bureau, reported early Thursday that 12,391 people have died in Turkey alone from the quake.

Syria's health ministry, meanwhile, has calculated the death toll in government controlled areas in Syria at more than 1,200. The White Helmets responders group based in Syria's rebel controlled region in the northwest said at least 1,600 people had died.

Summary of Turkey-Syria earthquake events on Wednesday

Turkey's Foreign Minister Mevlut Cavusoglu said his country is working to open two additional border gates to Syria to enable humanitarian aid into the war-torn country.

European Commission President Ursula von der Leyen said a donor conference for international aid for Syria and Turkey in the wake of Monday's devastating earthquake has been planned for March.

For the first time in 24 years, the Istanbul stock exchange announced that it is closing for five days in response to the earthquake.

Turkish President Recep Tayyip Erdogan, who visited the disaster area, acknowledged "shortcomings" in his country's response to the huge earthquake.

The sanctions-hit Syrian government has put in an official request to the EU for emergency assistance through the civil protection mechanism, the bloc's commissioner for crisis management has said, DW reports.