(Bloomberg) -- President Recep Tayyip Erdogan threatened to send millions of Syrian refugees settled in Turkey to Europe, as he bridled at criticism of his military offensive against Kurdish fighters.

“If you try to define our operation as an invasion, then our job becomes easy,” Erdogan said on Thursday at a gathering of his ruling party in Ankara. “We open the gates and send the 3.6 million refugees to you.”

The president has stepped up attacks in recent months on a deal he struck with the European Union, which included Turkey receiving 6 billion euros ($6.6 billion) in aid and other as yet undelivered enticements in return for preventing the movement of migrants. But the stinging condemnation of Turkey’s incursion into northern Syria this week has provoked Erdogan’s harshest reaction in years.

“Those who turn a blind eye to all the developments in Syria and make a habit of only criticizing Turkey -- we invite them to reason, conscience and morality,” he said.

Turkey sees the Kurdish militia as a threat to its security due to its links to separatist Kurds battling the Turkish military. It wants to drive the group from a border zone and then resettle at least 1 million displaced Syrians on the strip of territory.

But European officials and others have denounced the offensive for opening another front in Syria’s conflict and potentially fracturing international efforts to defeat Islamic State. Thousands of Kurdish fighters died taking a lead role in dismantling the jihadist caliphate.

Migration to Europe has dropped off dramatically since more than a million asylum seekers entered the bloc four years ago, above all to Germany. But not before the influx redrew the EU’s political map, driving a wedge between member states and fueling a rise in far-right populism that exploited social anxiety in the aftermath of the financial crisis.

There has been a recent swell of asylum seekers crossing the western Aegean Sea, a sign of trouble in the arrangements hashed out with Turkey that eventually staunched the flow of arrivals during the crisis of 2015 and 2016.

A new influx, even if nowhere near the same scale, has the potential to stir up trouble for European leaders such as Germany’s Angela Merkel, who suffered from the populist backlash against her open-door policy.

--With assistance from Taylan Bilgic.

To contact the reporter on this story: Onur Ant in Istanbul at oant@bloomberg.net

To contact the editors responsible for this story: Alaa Shahine at asalha@bloomberg.net, Mark Williams, Onur Ant

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