The European Union is determined to protect its borders, the bloc's chief diplomat said on Wednesday, as Greece accused Turkey of encouraging a fresh surge of migrants into Europe.
Josep Borrell made the comments as he visited the Evros border area, the scene of clashes in March after Turkey said it would no longer prevent migrants from reaching the EU.
After accompanying Borrell to the border, Greek Foreign Minister Nikos Dendias said Turkey had "once again declared that its land borders to Europe are open" following a brief respite during the pandemic.
"At the same time, its coastguard escorts boats laden with migrants to the Greek islands," Dendias said.
"But it also persists in undermining security and stability, as well as peace, in the Eastern Mediterranean."
Turkey did not immediately respond to the allegations.
Borrell said the European Union was "determined to protect the EU's external borders and strongly support Greece's sovereignty", according to state news agency ANA.
"We share your concern, we discussed how we could stop the dynamics of escalation," Borrell added.
At a later meeting with Greek Prime Minister Kyriakos Mitsotakis, Borrell said he wanted "trust and a dialogue" with Turkey to help stabilise the region.
"In order to build a relationship of trust, it is important that Turkey stop its provocative actions which clearly infringe on the sovereign rights of Greece," Mitsotakis said.
In late February, Turkish President Recep Tayyip Erdogan said he would let migrants wishing to get to the EU to travel through the country.
Thousands of migrants flocked to Greece, many gathering in the Evros border area or taking makeshift rafts to Greek islands.
For days, there were skirmishes on the border as migrants tried to break through, throwing stones at Greek riot police who responded with tear gas.
The leaders of the EU's three institutions -- Commission President Ursula von der Leyen, Council President Charles Michel and Parliament President David Sassoli -- visited the area at the height of the crisis.
Greece is among several regional states at odds with Turkey over energy drilling in the eastern Mediterranean, and over the conflict in Libya.
Mitsotakis has said the EU must not look "weak" in enforcing a UN arms embargo on Libya, after Turkey thwarted separate French and Greek attempts to inspect a Tanzanian-flagged cargo vessel suspected of carrying arms to Libya.