Outgoing European Council President Donald Tusk has sharply criticized Turkish President Recep Tayyip Erdogan's threat of "opening the gates" and "sending 3.6 million refugees your way" if the EU labels Turkey's incursion into Syria as an "invasion."

"Turkey must understand that our main concern is that their actions may lead to another humanitarian catastrophe," Tusk said at a press conference in Nicosia and on Twitter.

"And we will never accept that refugees are weaponized and used to blackmail us," he added, referring to an EU agreement with Ankara on refugees, struck in March 2016 as a result of a wave of migration to the bloc. 

"President Erdogan's threats of yesterday are totally out of place," he added.

Tusk said the current military operation in northern Syria was of "grave concern" and urged Ankara to stop the incursion. On Thursday, a UN Security Council meeting failed to agree on a joint statement on Ankara's move, with EU members condemning the move but Russia unwilling to sign the statement.

NATO more cautious

Meanwhile, at a meeting with Turkish Foreign Minister Mevlut Cavusoglu, NATO Secretary-General Jens Stoltenberg was more circumspect, pointing out that no ally in NATO had suffered more terrorist attacks than Turkey and that NATO was strongly committed to Turkey's security.

Read more: Explained: Why Turkey wants a military assault on Syrian Kurds

Stoltenberg added that he had shared his "serious concerns about destabilizing the region" and had told Ankara "to act with restraint," but stopped short of openly criticizing the NATO member.

Cavusoglu had earlier said that Ankara expects to see its NATO allies stand by it in the "legitimate" offensive in northeastern Syria. "It is not enough to say, 'We understand your legitimate concerns.' We want to see loud and clear solidarity," he said.

Russia worried about IS militants at large

Also on Friday, Russian President Vladimir Putin said he was worried that as Turkish forces attack Kurdish troops, IS militants there would be able to "simply run away."

"I am not sure whether the Turkish army will be able to bring this under control," Putin warned.

Read more: Opinion: The Kurds lose out again

Tens of thousands displaced

The UN's World Food Programme has warned that 70,000 people have already been displaced since the Turkish incursion was launched this week, particularly in the provinces of al-Hassakeh and al-Raqqa.

Turkish forces, meanwhile, pushed deeper into northeastern Syria on Friday, with casualties on both sides. Turkey reported its first military fatality, saying a soldier was "martyred" in the fighting. 

ng/tj (dpa, AP, Reuters)

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