In response to Europe’s immigration crisis, the German federal government has decided to unilaterally reintroduce border controls, temporarily overriding the stipulations of the Schengen Agreement, which abolished internal borders and passport controls for the 26 participating states.

According to the German magazine Der Spiegel, at 5:30pm Sunday, German Interior Minister Thomas de Maizière will hold a press conference in Berlin to formally announce the plan. The key issue provoking the move is the continuing high numbers of migrants crossing the border from Austria into Bavaria.

Until further notice entering Germany will require valid travel documents. Federal police are sending all available officers to Bavaria to close the borders. On Sunday morning federal riot police were sent to the German-Austrian border, fearing clashes with demonstrators.

The decision comes in the midst of some dramatic events at Munich train station this weekend, as well as a growing reaction within Germany opposing Angela Merkel’s decision last week to allow unregistered refugees to enter the country.

On Saturday, over 13,000 refugees arrived at the station on trains from Austria, with another 1,400 arriving on Sunday morning. The mayor, Dieter Rieter, said Munich was “full,” and that its capacities were completely overwhelmed. Some migrants slept Saturday night on the station concourse.

According to de Maizière, the new measures are in accordance with the provisions of the Schengen Borders Code, adding that they are indispensable for the maintenance of security and order, given the immense number of refugees.

The federal government has said it needs time to cope logistically with the large crowds of migrants. Bavaria has been particularly affected by the onslaught, but so has the North Rhine-Westphalia region, where tens of thousands of migrants have transferred in recent weeks. Germany also wishes to send a signal to possible refugees, that entry into the country is not a given.

Der Spiegel reports that the German government is considering using German soldiers as well for border security, backing up the federal police.

This is not the first time the Schengen Agreement has been temporarily suspended in Germany, with controls reinstated most recently for the G-7 Summit held in the Bavarian Elmau Castle last June.

Last month de Maizière warned he could not rule out a suspension of the Schengen agreement, adding that it was time other European countries took greater responsibility for the migrant crisis, especially Great Britain.

While Greece and Italy have been the first port of entry for the majority of immigrants and refugees, Germany has continued to carry the brunt of those seeking permanent residence. This year alone Germany expects up to 800,000 people to seek asylum, far more than in any other EU nation.

Last week Germany’s foreign minister Frank-Walter Steinmeier warned that the influx of hundreds of thousands of migrants could be “the biggest challenge for the EU in its history.”

“If we are united in describing the situation as such, we should be united that such a challenge is not manageable for a single country,” he said.

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