"We demand clear answers as to why, a month after the two soldiers were arrested, we do not know what they are charged with," government spokesman Dimitris Tzanakopoulos told reporters.

"This is a stance of obstruction that gives the impression that Turkey is trying to exploit the issue in order to exert political and diplomatic pressure. We do not consider this legitimate," Tzanakopoulos said.

Turkish media have reported that the pair, arrested on March 2 for entering a military zone in the northern Turkish province of Edirne, have been charged with espionage.

But Athens contends that Turkish authorities have not given adequate detail of the charges and on what evidence they are based.

On Tuesday, the Edirne court rejected a fresh appeal by the soldiers' Turkish lawyers for their conditional release, the private Dogan news agency reported, without providing any details.

The judgement was announced after Turkish President Recep Tayyip Erdogan came under pressure from EU chiefs at a meeting in Bulgaria on Monday to release the pair.

European Commission chief Jean-Claude Juncker said the bloc's 28 member states had confidence in the Turkish side "to solve that (the issue of the soldiers) in the best way".

An EU meeting in Brussels last week condemned Turkey over the soldiers' arrest in a show of firm support for Athens.

The soldiers told prosecutors shortly after their arrest that they mistakenly crossed the border after getting lost in the fog.

But according to Turkey's state-run Anadolu news agency, they have been charged with "attempted military espionage" by prosecutors as well as entering a forbidden military zone.

It said the pair testified they entered the Turkish side by tracking footsteps in the snow and filmed images on their mobile phones to send to higher ranking officials.

The arrest of the soldiers have strained ties between Ankara and Athens, who are already at loggerheads over the exploration of gas reserves in the eastern Mediterranean.

The long-standing foes have also clashed over Turkish demands that Greece extradite eight Turkish troops wanted over the July 2016 attempted coup aimed at unseating Erdogan.

burs-jph/bp