A former airport that was converted into an emergency shelter for migrants and refugees in Berlin is seen on Feb. 25. (Rainer Jensen/European Pressphoto Agency)

A contentious deal struck Friday between the European Union and Turkey aims to finally halt the historic wave of irregular migration to Europe from the Middle East and beyond. But Germany, ground zero of the refu­gee crisis, faces a separate problem — what to do about all those who are already here.

The rapid rate of arrivals in the once-welcoming nation has forced a backlog of 770,000 asylum requests. About half of them, authorities say, will be rejected. That means figuring out how to get the asylum seekers who cannot stay to leave. With deportations on such a scale seen as problematic at best, the country has come up with a solution: Pay — some say bribe — them.

By the time his offer came, Lauand Sadek was already regretting his arduous trek from Iraq to Germany.

A month had passed since he arrived in the promised land of migrants, yet the 21-year-old was still stuck in a crowded refugee camp. Unable to speak German, he hardly went out. Then this overwhelmed nation made him an interesting proposition: Go back home, and we’ll help build you a better life there.

“I was alone and confused,” Sadek said via Skype from Iraq, where he voluntarily returned in December. He made the choice after the German government offered him a plane ticket and up to 6,000 euros (roughly $6,540) to invest in a small business — a little grocery store in Irbil.

European Union leaders welcomed Turkey's offer to take back migrants crossing into Europe from its soil, in exchange for more aid, faster E.U. membership talks and a conditional promise of visa-free travel. (Reuters)

“I would have stayed in Germany longer, but their offer helped me understand,” he said. “It was time to go.”

[After hard journeys to Europe, who gets to stay?]

The offer suggests the philosophy being embraced on this side of the Atlantic, where mass deportations are considered not only a last resort, but also a less effective tool than persuading migrants to choose to leave. Pointing to the many Mexicans who are deported from the United States but soon try to make their way back, the Germans and some of their European neighbors are also seeking ways to coax migrants to leave permanently.

“If you move me because I’m starving and I’m sent back and I’m still starving, then I’ll just try again,” said Eugenio Ambrosi, European Union director of the International Organization for Migration.

Germany, with its Nazi and Cold War memories of police state violence, is known for its gentle treatment of illegal migrants. And in years past, legal loopholes and other means of delay meant that few were deported.

But the challenge the country faces today is unprecedented. Chancellor Angela Merkel’s open-door stance for those fleeing war in the Middle East turned it into a magnet. In addition to the would-be refugees from Syria and Iraq, job seekers from Morocco and Bangladesh flocked here with stories of persecution back home. The latter stand almost no chance of winning legal asylum.

To push them out, Germany’s answer encompasses both threats and inducements, including offers of extra cash, business investment grants, even the promise of vocational training if migrants agree to voluntarily go home.

1 of 12 Full Screen Autoplay Close Skip Ad × Migrants get stuck in Greece as door closes to Europe View Photos After a year and a half of massive migration to the continent, some nations along the route are saying no. Caption After a year and a half of massive migration to the continent, some nations along the route are saying no. March 1, 2016 Yazidi asylum seekers from Shengal, Iraq, rest outside an Ikea house at the Diavata migrant camp recently built by Greece on the outskirts of Thessaloniki. Jodi Hilton/For The Washington Post Buy Photo Wait 1 second to continue.

[For better or worse, a refugee assembly line in Germany]

Under an incentive plan for Iraqis, for instance, Sadek received the equivalent of $1,000 up front and stands to get $5,400 more in the coming weeks once his business plan for a grocery store is finally approved. Nearly 100 other Iraqis have received promises of English classes and money to open restaurants or other businesses. Under a pre-existing but expanded program, more than 5,000 Kosovars over the past two years received up to 3,000 euros — about $3,300, or nearly nine months’ worth of the average salary in Kosovo — to return.

For Germany, the emphasis on voluntary returns could also prevent what would otherwise be politically damaging scenes at airports if vast numbers of distraught migrants were suddenly sent packing via mass deportations.

“Compared to the United States, Germany is soft,” said Dietrich Thränhardt, a migration expert at Münster University. “They don’t want to act too dramatically.”

It’s not all Mr. Nice Guy.

German authorities are also forcibly repatriating more people, with expedited processing of economic migrants masquerading as refugees. After targeting nationals from Balkan nations, they are now focusing on North Africans and Afghans with weak cases for asylum. The number of migrants deported from Germany rose to 20,888 in 2015, almost double the number in 2014.

Still, far more migrants in Germany went back home willingly last year than were deported — at least 37,000. Compare that to, say, France, where deportations in 2015 outpaced voluntary returns by a margin of 3 to 1.

Germany is relying on voluntary returns because, in many cases, that is the only way to get rid of migrants. Since Merkel’s famous welcome speech last year, nationals from a dizzying number of countries have crossed German borders, with many destroying their passports to make it harder to send them back.

Some nations, particularly in West Africa and parts of Asia, are refusing to take back their citizens without solid proof of identity. In December, Pakistan sent 30 deported migrants back to Europe because, it said, it could not determine if they were really Pakistani.

“In the months to come, we will have a few hundred thousand people who are supposed to leave the country, and the sheer dimension means that removal cannot be the first option,” said Christian Klos, head of the migrant law division at Germany’s Interior Ministry. “They will be counseled to leave voluntarily.”

The Germans have, however, struck deals with Morocco, Algeria and Tunisia to help them identify and take back their nationals without passports.

At the same time, the Germans are trying to reduce the appeal of life here as a migrant. This week, new rules came into effect forcing some migrants under humanitarian protection to wait at least two years before bringing in close family members, even from war-torn countries.

Critics argue that after years of being too lax, German authorities are now overcompensating — pressuring migrants to go home voluntarily with tactics that effectively amount to coercion.

[Germany seeks North African help to speed migrant deportations]

Ahmadshakeb Baloch, a 26-year-old Afghan who said he arrived in Germany six years ago because he was under threat from the Taliban, had begun to build a new life in Bavaria. He learned German and became a restaurant cook and security guard.

But asylum rulings are now being sped up and are likelier than not to be negative. After five years, Baloch finally received word in 2015 that his application had been rejected. He appealed, and received a speedy notice he had lost. His work visa was also revoked.

Without a job, he now survives on 320 euros a month in state aid — not enough, he says, to keep sending money home to his parents. Authorities, he said, seized his driver’s license and identification card and have ordered him to obtain a valid passport from the Afghan Embassy.

But Baloch said he is terrified that, if he does, the authorities will rush him to the airport and put him on a plane to Kabul. In recent months, the Germans have stopped giving advance notice on deportation dates.

“I wanted a new life, but they are making it so difficult for me here,” Baloch said, fighting back tears. “I sit by the window all day and think and cry and think. I won’t go back.

“I will die in Germany.”

Stephanie Kirchner in Berlin and James McAuley in Paris contributed to this report.

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E.U. strikes deal to return new migrants to Turkey

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