An influx of people crossing into Turkey from Iran in recent days, many of them Afghans fleeing conflict, sparked renewed anti-migrant sentiment and raised questions over the future of the 4 million refugees living in the country.

Turkish media has shown images of lines of mostly young men crossing mountain paths into Turkey’s eastern Van province.

About 1,200 people are believed to be crossing the frontier each day. Many of the refugees interviewed said the exodus was spurred by the Taliban’s advance as the US began withdrawing its forces in Afghanistan before its September 11 deadline.

The new influx will put pressure on the assistance programmes for migrants already living in Turkey, which has the world’s largest refugee population.

It also poses questions over the 2016 refugee deal struck between Ankara and Brussels which kept migrants from travelling on to the EU in exchange for concessions and €6 billion in aid for Syrians in Turkey.

That deal was intended to prevent a repeat of 2015, when more than a million people – mostly refugees from Syria – crossed into the bloc’s member states, throwing its vision of borderless integration into disarray.

Although dwarfed by the number of Syrians in Turkey, Afghans make up the second-largest migrant group, with a conservative estimate of 200,000 in the country.

More Afghans than any other nationality are currently being detected crossing the Aegean Sea, according to the Turkish Coast Guard, which said on Wednesday it had stopped a boat carrying more than 200 Afghans believed to be heading for Italy.

This month, the Van governor’s office said more than 27,000 people had been intercepted crossing the Iranian border since the start of the year.

“Domestically, Turkey has not supported [the non-Syrian migrant] population but they also haven’t been encouraged to do so by the international community, in particular Europe, except, of course, for keeping them from entering Europe,” said Susan Fratzke, senior policy analyst at the Migration Policy Institute in Washington.

“We’re not in a very good position right now to respond because of either that lack of political investment on the part of Turkey or financial investment internationally.”

Turks have become increasingly disillusioned with the 2016 deal because it has failed to deliver on pledges to ease Turkey’s EU accession and cut EU visa restrictions, while placing the refugee burden on Turkey’s shoulders.

Coverage of the latest migration surge from Afghanistan seems to have sparked renewed anti-migrant sentiment, which is reinforced by the feeling that Turkey’s generosity towards refugees is being abused by the West.

In a tweet written in English on July 18, Kemal Kilicdaroglu, leader of the opposition Republican People’s Party (CHP), shared his “call to the world” in which he said no one could “declare my country an open prison to refugees”.

In response to comments from Austrian Chancellor Sebastian Kurz, who said on Sunday that “states like Turkey ... are definitely a better place [for refugees] than Austria, Germany or Sweden,” the Turkish Foreign Ministry said: “Turkey will not be a border guard or a refugee camp for the EU.”

Meanwhile, when Tanju Ozcan, the CHP mayor of Bolu province in north-west Turkey, announced a plan this week to charge refugees 10 times as much for water and waste services, and said that Turkey had “become a dump for migrants”, his remarks were welcomed by many Turks.

“A wave of xenophobia and racism is ruining the lives of refugees in Turkey,” said Dr Dogus Simsek, a lecturer at Kingston University London, whose research focuses on migration and refugees.

“They are seen as criminals, stealing jobs and being responsible for anything that goes wrong.”

Metin Corabatir, president of the Ankara-based Research Centre on Asylum and Migration, said: “This issue has become a hot political topic, which creates new tensions. The opposition use it for short-term interests, which is very dangerous.”

The 2016 agreement remains the preferred option for EU leaders. European Commission President Ursula von der Leyen said during a visit to Ankara in April that the deal “remains valid and has brought positive results”.

Turkish officials have called for the agreement to be updated; a demand given greater urgency by the arrival of migrants from the east.

“Both the EU and Turkey want this deal to continue,” Mr Corabatir said. “Turkey would like to include other elements, such as visas and the changes to the customs union, in the package. I think the EU side want to give money, but in a more restricted way.”

Others said Turkey was in a better negotiating position, given the bloc’s obvious priority in keeping large numbers of refugees out.

“The relationship is such now that I’m not sure what other incentives the EU will be able to offer Turkey, given the reluctance of the Greek government to be conciliatory towards Turkey,” Ms Fratzke said.

“While money is nice, Turkey is hosting a lot of people right now and the expansion of resettlement would be useful.”

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