A Turkish judge on Monday rejected an appeal by the lawyers of two Greek soldiers, who accidentally crossed the border last Thursday, for their release from custody in Edirne.
The two soldiers had been remanded in custody pending trial on charges of illegal entry. But the lawyers had appealed against their detention.
The next move is for the Turkish court to determine which charges the Greek soldiers are to face and for a trial date to be set.
The soldiers' lawyers are hoping that a judge will not extend their charges to include espionage.
Relatives of the two soldiers were permitted to visit them in custody on Monday.
Earlier in the day Greek Foreign Minister Nikos Kotzias called on Ankara not to create a "a big legal and political problem" out of the Greek soldiers' case.
"Turkey must enforce what is foreseen by international law and not turn an everyday procedure into a big legal and political problem," Kotzias said during a press conference on Monday with his Cypriot counterpart Nikos Christodoulides.