Germany has seen an immense drop in the arrival of asylum seekers, with the total number in 2016 down to less than a third of the 890,000 who arrived in 2015, according to the interior minister.

Thomas de Maiziere said on Wednesday that about 280,000 new asylum seekers arrived in 2016, while an estimated 80,000 people either left voluntarily or were deported.

The minister said authorities hoped the number of those who leave or are deported will increase.

Arrivals declined sharply with the closure of the Balkan refugee route in March and the subsequent agreement between the European Union and Turkey to stem the flow across the Aegean Sea to Greece.

Asylum applications have lagged well behind arrivals and many people who came to Germany in 2015 applied only last year.

Wednesday's figures showed that 745,545 formal asylum applications were made last year - 268,869 more than in 2015.

Those included 268,866 applications from Syrians, 127,892 from Afghans and 97,162 from Iraqis, the biggest single groups by far.

The Federal Office for Migration and Refugees, which has been beefed up in the course of Europe's refugee crisis, decided last year on more than 695,000 asylum applications, more than twice as many as in 2015.

Nearly 60 percent of applicants were granted either full refugee status or a lesser form of protection.

Deportations and returns

The agency has also cut the average time required for an asylum decision to under three months, and introduced a nationwide database to combine identity records for all asylum seekers.

De Maiziere said that about 55,000 failed asylum seekers returned home voluntarily last year, compared with the previous year's 35,000. Another 25,000 were forcibly deported.

Chancellor Angela Merkel, who faces a national election later this year and still draws criticism for her welcoming approach to refugees and migrants in 2015, has promised a "national effort" to ensure that people who are not entitled to stay go home.

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The number of returns is still too low, de Maiziere said, adding that talks are under way with state authorities - who are responsible for returns - to push it up.

De Maiziere rejected the suggestion that the drop in new arrivals was the result of Europe's efforts to prevent people reaching the continent, but acknowledged that Germany was working to ensure that refugees stay in their home region.

Trapped in cold

Closed borders across Europe have left refugees and migrants trapped in difficult humanitarian conditions in the Balkans, Greece and elsewhere.

Rights groups have expressed concern about the fate of refugees and migrants as a wave of cold weather grips the region.

In Serbia, hundreds of refugees and migrants were living in abandoned buildings behind the train and bus station in the city centre.

Temperatures have dipped as low as minus 20 degrees Celsius, while access to humanitarian aid has been limited by a ban imposed by the government.

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"In some cases, not only have authorities failed to provide humane conditions, they have also tried to prevent humanitarian organisations from aiding those in need," said Human Rights Watch in a statement last week.

In camps across mainland Greece and Greek islands, refugees and migrants have struggled as temperatures have sunk as low as minus 18 degrees in recent days.

In Moria, a camp on the island of Lesbos, more than 4,500 people who live in tents are among those hit the hardest by the snowy weather.