The change in course of River Evros has caused a dispute on territory between Turkey and Greece, a foreign ministry source said Friday.
The ministry official confirmed an earlier report by state agency ANA, saying Athens had made a protest to Ankara.
River Evros changes course: dispute arises
Foreign Minister Nikos Dendias on Wednesday said there was a “dispute” over the “exact boundary” of the Evros, the river known as Maritsa in Turkey that divides the two countries.
“The riverbed has changed,” Dendias said.
Greek reports on Friday said Turkish troops had occupied a strip of land that is normally submerged at this time of year, and is on Greece’s side of the border.
The main opposition Syriza party on Friday demanded an immediate briefing “over Turkey’s arbitrary and aggressive actions”.
Read more: Greece Complains to Turkey Over Border Riverbed Dispute
Dendias was criticised in parliament for saying on Wednesday that “all these things can be resolved via a joint committee and the relevant measurements.”
“We’re talking about a few tens of metres,” he said.
We are ‘prepared’ for Turkey: Greece Defence Minister
After the barrage of air and sea challenges from Turkey, the Greek Minister of Defence emphasised that an accident in the Aegean Sea may be very close and sent a message to Ankara saying that “as vigilant guards we strengthen our borders, prevent and stop.”
Defence Minister Nikos Panagiotopoulos spoke about the Turkish provocation yesterday, when the Turkish coastguard harassed Greek fishermen near the island of Oinousses, noting that there is a fear of an accident as there is too much activity in a very small space.
“We expect good faith, better behaviour,” he said, adding that “there are no good neighbourly terms at the moment.”
“We are in a good mood, we want the other side to show that the channels of communication must be open,” Panagiotopoulos said, adding: “I don’t think Turkey wants to escalate tensions until other situations arise, but behavioural patterns make us look at all possibilities and prepare.”
Turkey-Greece tensions heightened amid escalating row
There was tension in the area in March after Turkey encouraged tens of thousands of asylum-seekers to travel to the border with Greece in the hope of crossing into the European Union.
For days, there were skirmishes on the border as migrants trying to break through threw stones at Greek riot police who fired tear gas at them.
Turkish police also bombarded Greek forces with tear gas at regular intervals, and Athens accused Turkish police of handing out wire cutters to migrants to help them break through the fence.
Read more: Activists held in Greece for illegally aiding Migrants
Greek border forces have also claimed that Turkish troops have recently fired shots into the air.
Ankara accused Athens of beating migrants and firing live rounds at them, alleging that some died of bullet injuries.
The Greek government categorically denied using undue force.
AFP with additional input by GVS News Desk