Greece's Prime minister Alexis Tsipras arrives to the European Council headquarters on the first day of a summit of European Union (EU) leaders at the in Brussels (AFP)
Greek Prime Minister Alexis Tsipras on Saturday demanded the release of two soldiers jailed in Turkey, arguing that they should not be "pawns to blackmail."
"Human life and human freedom are not, and should not be, pawns to power games and blackmail," Tsipras said in a statement to Documento newspaper.
Turkey is holding in pre-trial detention two Greek soldiers who crossed the border on 2 March, claiming to have lost their way in the fog.
Greece had hoped to secure their release before Sunday's Orthodox Easter celebration.
Turkish media have reported that the pair, held in the northern Turkish province of Edirne, have been charged with espionage.
But Athens contends that Turkish authorities have not given adequate details of the charges and on what evidence they are based.
According to Turkey's state-run Anadolu news agency, the soldiers have been charged with "attempted military espionage" as well as entering a forbidden military zone.
The issue has strained an already tense relationship between the two NATO allies and regional rivals.
Turkish President Recep Tayyip Erdogan and members of his government have escalated attacks on Greece after its failure to extradite eight Turkish soldiers that Ankara said were part of an attempted 2016 coup.
The Greek Supreme Court has conclusively blocked the extradition of the eight Turkish soldiers, arguing that they would not have a fair trial in their home country amid an ongoing purge of suspected Erdogan opponents.
Additionally, Ankara and Athens are at loggerheads over the exploration of gas reserves in the eastern Mediterranean.
Tsipras earlier this week called on the Turkish judiciary to "speed up" its processing of the case.
"In the past, we returned Turkish soldiers who crossed a few metres into Greece whilst on patrol. I expect the Turkish president to do the same," he said.
Turkish Prime Minister Binali Yildirim on Wednesday said Turkey would "do what it must" over the soldiers and criticised Greece's decision to raise the issue with the EU.
“It has become a habit [for Greece] to take any issue it has with Turkey to the EU to ask for its support,” Yildirim said, during a visit to Turkish occupied northern Cyprus.
“Our relationship with the EU will neither advance nor deteriorate because of such actions.”
He also slammed the burning of the Turkish flag during a demonstration against the soldiers' detention held by the far-right Golden Dawn party on Monday.
“Our flag is our honor. We cannot tolerate any attack on it,” he said.
“We want the Aegean to be a sea of friendship and such provocation does no good.”