"This is pure fantasy. We are not at war with Turkey to conduct an exchange of prisoners," junior minister Yiorgos Katrougalos told reporters on Saturday, adding that such "spy stories" originated in Turkish media reports.

"This is not an unusual episode. Such incidents occur on the border," he said, according to state agency ANA.

Two Greek soldiers were arrested by a Turkish border patrol inside Turkish territory on Thursday.

The Greek army said the pair, a lieutenant and a sergeant, lost their way in poor weather while patrolling the area around the Evros river that separates the two countries.

ANA said the soldiers, who are held at Edirne, will be put on trial on Monday.

Athens insists that they will be tried for illegal entry in a restricted area, but Turkish state agency Anadolu has reported that attempted military espionage is among the charges.

Greek government spokesperson Dimitris Tzanakopoulos on Friday said that the case was one of "illegal entry" and said Athens expected the "imminent return" of the two Greek officers.

The incident risks exacerbating tensions between Ankara and Athens, who have come to the brink of war on several occasions in past decades, despite being NATO allies since 1952.

Turkish and Greek vessels have in the last weeks twice collided off Aegean islets that have been a historic flashpoint in a long-running demarcation dispute.

Another festering sore is Cyprus, where the northern portion of the island is still occupied by Turkish troops following the 1974 invasion in response to an Athens-inspired coup aimed at uniting it with Greece.

Tensions over Cyprus are high as Turkey vows to block any moves by the internationally recognised Greek Cypriot government to exploit oil reserves off the Mediterranean island.

But of most immediate concern to Ankara is the presence in Greece of suspects wanted by Turkey on charges linked to the 2016 failed army coup.

The Athens authorities have failed to hand over eight Turkish troops who escaped to Greece by helicopter on the night of the putsch, saying they would not have a fair trial at home.

burs-jph/ecl