Top German and EU officials traveled to Turkey ahead of a trip to Greece for talks on how to manage the flow of migrants to Europe.

The high-level trip comes as a deal between the European Union and Ankara to reduce the number of migrants reaching Greece from Turkish soil appears to be in trouble, with Turkish President Recep Tayyip Erdogan threatening to "open the gates" for migrants to head Europe if his conditions are not met.

Turkey's Foreign Minister Mevlut Cavusoglu described Friday's meeting as "productive and "frank" but said there was only a "small increase" in migrant arrivals in Greece and that criticism of Turkey over its migration management was "baseless."

His comments were aimed at French President Emmanuel Macron who criticized Turkey earlier this week over the issue. Cavusoglu said Macron's accusations "are not acceptable" and called on European nations to work with Ankara on solving the refugee crisis instead of blaming it for an increase in migration to Europe.

"We saw that they (Germany) are intent on a healthier cooperation with Turkey on this (migration) issue," said Cavusoglu of his meeting with German Interior Minister Horst Seehofer and EU Migration Commissioner Dimitris Avramopoulos in Ankara.

Greece is facing overfilled refugee camps on the Aegean Islands, where human rights groups have criticized the poor living conditions and warned of the coming winter.

"Irregular arrivals to Greece increased over the past weeks and months,"  said Avramopoulos. "There is an urgent need to further strengthen the prevention and detection of irregular departures from Turkey."

Seehofer said after meeting with his Turkish counterpart that Turkey faced "enormous" migratory pressure, which has increased with new arrivals from Afghanistan and Syria. There are around 3.6 million Syrian refugees in Turkey. 

"And that is why we must look at how this pact between the European Union and Turkey can be strengthened," Seehofer said, adding that additional financial support for Turkey was on the table. 

Under a 2016 EU-Turkey agreement, Turkey committed to preventing migrants from reaching Greece. Greece was also permitted to send rejected asylum-seekers back to Turkey. In return, Turkey was pledged €6 billion ($6.6 billion) to house refugees in camps, while the EU also accepted a certain contingent whose asylum claims had been recognized. So far €5.8 billion has been allocated and €2.6 billion disbursed.

Read more: How the EU-Turkey refugee deal works

Turkish maneuvering 

But Erdogan has complained that his country has so far received too little of the €6 billion promised by the EU for the years 2016 to 2019, while shouldering costs of more than €36.5 billion at a time the Turkish economy is struggling. 

EU staff in Turkey say, however, that under the deal, the funds are released only in connection with concrete projects, something they say is not fully accepted by Turkish government officials.

Erdogan is also playing the refugee card to ramp up pressure on Europe to support a plan to resettle nearly a million Syrians from Turkey into a controversial "safe zone" in northeastern Syria. There, the Turkish military is in fraught cooperation with the US military to clear a section of the border of Kurdish forces that fought the "Islamic State" and are viewed as a threat by Ankara.

Critics of the plan say Turkey intends to ethnically cleanse the predominately Kurdish populated area along the border by replacing them with Syrian Arab refugees.  

Separately, Ankara has warned it could face a massive influx of up to 3 million Syrians if Russian-backed Syrian government forces press an offensive in the last rebel enclave in northwest Idlib province. 

Migrant numbers on the up again

The official EU trip comes as the number of migrants reaching the Greek islands is on the increase once more, though the flow is much reduced compared with 2015 levels, when up to 7,000 people arrived on some days. More than 30,000 migrants are now being hosted on the islands, up from 14,000 in April.

However, the leftist government of former Greek Prime Minister Alexis Tsipras returned just some 2,000 people, despite overcrowding on several islands. The island of Lesbos, for example, is hosting some 13,000 migrants, although its reception center is designed for just 3,000. The new Greek government under conservative premier Kyriakos Mitsotakis is expected to take a harsher stance and return more people.

Read more: Greece's Moria fire exposes refugee camp pushed to limit

Ahead of Seehofer's trip, a group of human rights organizations called on the German government to take some of the burden off Greece by taking in young refugees from the Aegean islands.

A letter to Seehofer and Chancellor Angela Merkel signed by charities Pro Asyl and Terre des Hommes, among others, described the situation on the islands as a "considerable risk to children and young people."

"We therefore ask you to take in unaccompanied minor refugees from Greece and to use all existing legal means to reunite those seeking protection with family members in Germany," the letter said.

Leading members of Germany's Green party also had a message for Seehofer.

Its parliamentary spokeswoman for refugee affairs, Luise Amtsberg, and former party leader Claudia Roth called on him to make it clear to the Turkish government that returning refugees to Syria against their will, as Ankara is reported to have done by human rights groups, is a "blatant violation of laws on asylum."

Read more: Refugees in Germany: Legal entry — without asylum

mvb, cw, tj/cmk (AP, dpa, AFP)

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