STOCKHOLM — Stunned by an unprecedented wave of migration, a Swedish official on Thursday put into words an uncomfortable reality for Europe: If the continent isn’t going to welcome more than 1 million people a year, it will have to deport large numbers of them to countries plagued by social unrest and abject poverty.

Interior Minister Anders Ygeman said Sweden could send back 60,000 to 80,000 asylum seekers in the coming years. In a country with a long history of immigration, that would be a scale of expulsions unseen before.

‘‘The first step is to ensure voluntary returns,’’ Ygeman told Swedish newspaper Dagens Industri. ‘‘But if we don’t succeed, we need to have returns by coercion.’’

Packing unwilling migrants, even entire families, onto chartered airplanes bound for the Balkans, the Middle East, or Africa evokes images that clash with Europe’s ideals.

But the sharp rise of people seeking asylum in Europe last year almost certainly will lead to much higher numbers of rejections and deportations.

European Union officials have urged member countries to quickly send back those who don’t qualify for asylum so that Europe’s welcome can be focused on those who do, such as people fleeing the war in Syria.

‘‘People who do not have a right to stay in the European Union need to be returned home,’’ said Natasha Bertaud, a spokeswoman for the EU’s Executive Commission.

‘‘This is a matter of credibility that we do return these people, because you don’t want to give the impression, of course, that Europe is an open door,’’ she said.

EU statistics show most of those rejected come from the Balkans, including Albania and Kosovo, two of Europe’s poorest countries. Many applicants running away from poverty in West Africa, Pakistan, and Bangladesh also are turned away. Even people from unstable countries such as Iraq, Afghanistan, and Somalia can’t count on getting asylum unless they can prove they, personally, face grave risks at home.

Sending them back is easier said than done. In 2014, EU nations returned less than 40 percent of the people who were ordered to be deported. Sometimes those seeking asylum go into hiding after receiving a negative decision. Sometimes their native country doesn’t want them back.

EU countries have had some success sending people back to the Balkans on chartered flights. Of the 37,000 who returned from Germany on their own accord last year, all but about 5,000 were from the Balkans.

‘‘It’s been more difficult with Iraq and Afghanistan,’’ said Mikael Ribbenvik, director of operations at the Swedish Migration Agency. ‘‘The returns have worked during some periods, and not so well during others.’’

One of the biggest obstacles to sending people back is to obtain travel documents from their home countries. People routinely lose or even destroy their travel papers coming to Europe, creating confusion.