Germany announced Sunday that it was introducing temporary border checks on the Austrian frontier. Bavarian Premier Horst Seehofer said the decision was an "important signal" to the rest of the world as well as to Germans concerned about the "worrying" influx of refugees.

Germany and Austria agreed over a week ago to let in refugees who had gathered in Hungary, saying it was a one-time measure to ease an emergency. The influx has continued and, while Germans have remained welcoming, officials said over the weekend that the speed of the arrivals was straining the country's ability to provide accommodation.

"This step has become necessary," Interior Minister Thomas de Maiziere told reporters in Berlin. "The great readiness to help that Germany has shown in recent weeks ... must not be overstretched."

European Union interior ministers will meet on Monday amid deep divisions in the 28-nation bloc over how to handle the influx of refugees and others seeking a better life. Germany. The U.N. High Commissioner for Refugees said an EU response should include "the rapid implementation of a relocation program" to spread refugees among all EU countries. Many nations are resisting that.

Germany has called, so far with little success, for other countries in the 28-nation European Union to share the burden of taking in people seeking refuge. Its move came a day before a meeting of EU interior ministers, and de Maiziere said it was "also a signal to Europe: Germany is facing up to its humanitarian responsibility, but the burdens connected with the large number of refugees must be distributed in solidarity within Europe."

De Maiziere didn't specify how long the border controls would remain in place or give details of exactly how incoming migrants would be handled. He said there could be disruption to rail travel. Most migrants have been arriving by train.

The rules of Europe's passport-free travel zone, known as the Schengen area, allow countries to reintroduce controls in exceptional circumstances, and the European Commission said that "the current situation in Germany ... appears to be a situation covered by the rules."

Germany has become the destination of choice for migrants, particularly Syrians, after Chancellor Angela Merkel relaxed asylum rules for citizens of the war-torn country. But with 450,000 migrants arriving since the beginning of the year, infrastructure in Germany is being stretched to the limit.

Munich mayor Dieter Reiter vowed on Sunday to not give up in the face of the daunting challenge posed by a record influx of refugees.

"The night was long. We managed but we need a regulated, sustainable system to distribute the arriving refugees across Germany," he said, a day after 13,000 refugees poured into the southern German city.

"Every train that does not travel to Munich helps us," he said, adding quickly: "I am not easily depressed. I will not give up in any case."

Scenes of Germans waiting at Munich station, carrying "Refugees welcome" banners and clutching teddy bears to give to weary children after their long journey from war and persecution, have also become endearing images of the unprecedented refugee crisis hitting Europe.

"The generosity of the Munich people remains incredible," Colin Turner, a spokesman for volunteers at the Munich rail station, told Agence France-Presse. "Just five minutes after we launched our appeal yesterday on social networks for mattresses and sleeping bags, the first donations arrived. When I saw the amount of mattresses that the people brought and also all these people who came to help, I had tears in my eyes."

In Austria, meanwhile, authorities said they were receiving another wave of refugees coming over the border from Hungary on Sunday, after a brief lull in arrivals gave them a chance to re-stock reception centers.

Austria struggled last week to cope with thousands of people entering its territory, almost all of them on their way to Germany. The train link to Hungary has been closed since Thursday in a bid to stem the flow.

Only 50 people crossed the border early Sunday morning, but Hungarian authorities had said more were on their way and numbers could climb to 500 an hour, a spokesman for the Austrian police said. Austrian authorities were expecting 6,000 to 8,000 new arrivals through the day, the spokesman added.

Thousands of refugees are crossing into Hungary, an eastern outpost of Europe's passport-free Schengen zone, every day. Many are traveling on to the continent's more prosperous west and north in what is Europe's worst refugee crisis since the Yugoslav wars of the 1990s.

In Munich it was clear that the city's infrastructure to welcome the new arrivals was under severe strain. Some 63,000 refugees have arrived by rail at the main station since August 31, authorities said.

"Given the numbers from yesterday, it is very clear that we have reached the upper limit of our capacity," said a spokesman for Munich police.

Bavarian public television BR said the city "came very close to a humanitarian disaster,” although authorities managed to limit the numbers of people sleeping on mattresses on the floor to just a few dozen, rather than the hundreds as earlier feared.

Authorities are mulling whether to open up the Olympiahalle — a stadium used for the 1972 Olympics and which today serves as a concert hall or sports arena — as a temporary shelter for the refugees.

In a sign that authorities were running out of options, regular passenger trains will be cleared out to transport refugees instead. One such train linking Munich to Berlin will be affected Sunday, with passengers told to rebook their trains.

Other regular services will be requisitioned on Monday, as the southern German city seeks to rapidly transport refugees onwards to other locations across the country in order to free up space for new arrivals.

Elsewhere in the station, some refugees were queuing at the reception center, where they were to undergo medical checks before being sent on to shelters in the region or put on trains to other parts of Germany.

Al Jazeera and wire services