One of two hikers that became trapped on Mount Olympus has died while the second was successfully rescued in an operation mounted by the fire brigade to find them, Greek authorities said.

Only through cooperation, solidarity and respect to the international law and the international treaties as the Lausanne Treaty, we can live peacefully in the region of the Balkans, stated Greek Prime Minister Alexis Tsipras after the end of the 2nd quadrilateral summit between Greece, Bulgaria, Romania and Serbia that was held in Belgrade.

The United States of America supports the sovereignty of countries like Greece and Turkey as a matter of principle, the American government said in comments to Lena Argyri, national Greek broadcaster ERT's correspondent in Washington DC, concerning the Treaty of Lausanne.

The Lausanne Treaty is the cornerstone of Greek-Turkish relations, Greek Prime Minister Alexis Tsipras said during joint statements with Turkish President Recep Tayyip Erdogan on Thursday, after their meeting at the Maximos Mansion in Athens.