Wolfgang Schaeuble
German Finance Minister Wolfgang Schaeuble, pictured Nov. 20, 2015, said German courts had decided s refugees were not being treated humanely in Greece and could not be sent back. Ralph Orlowski/Reuters

German Finance Minister Wolfgang Schaeuble and a senior Bavarian politician criticized Greece on Sunday over the way it is managing its role in Europe's biggest migration crisis since World War Two.

Schaeuble, who has clashed repeatedly with Greek officials this year over economic policy, told Bild am Sonntag that Athens has for years ignored the rules that oblige migrants to file for asylum in the European Union country they arrive in first.

He said German courts had decided some time ago that refugees were not being treated humanely in Greece and could therefore not be sent back there.

"The Greeks should not put the blame for their problems only on others, they should also see how they can do better themselves," Schaeuble said.

Greece, a main gateway to Europe for migrants crossing the Aegean Sea, has faced criticism from other EU governments who say it has done little to manage the flow of hundreds of thousands of people arriving on its shores.

Joachim Herrmann, the interior minister of the southern state of Bavaria, that has taken the brunt of the refugee influx to Germany, criticized the way Greece is securing its external borders.

"What Greece is doing is a farce," Herrmann said in an interview with Die Welt am Sonntag newspaper, adding any that any country that does not meet its obligations to secure its external borders should leave the Schengen zone, where internal border controls have been abolished.

The EU's border agency Frontex has agreed to increase its presence in Greece at the end of the month, while European guards will help Greeks manage their frontier with Macedonia following concern over Athens' commitment to controlling migration.

Herrmann said it was also important to secure the border with Slovenia so that all people entering the Schengen zone from Croatia could be properly registered and potential terrorists spotted.

"If this is not guaranteed within a few weeks, we will have to become active on our own borders," he said.

Solidarity

In contrast to his criticism of Greece, Schaeuble sought to offer to compromise with eastern European countries that have voiced reluctance to accept migrants under EU quotas.

"Solidarity doesn't start by insulting each other," Schaeuble said. "Eastern European states will also have to take in refugees, but fewer than Germany."

The influx of hundreds of thousands of migrants, many fleeing war and poverty in the Middle East, also means that European countries will have to increase spending on defense, he said.

"Ultimately our aim must be a joint European army. The funds that we spend on our 28 national armies could be used far more effectively together," Schaeuble said.

Schaeuble said the Middle East would not become stable without stronger European engagement.

Germany has gradually adopted a more assertive role in global missions. Earlier this month, lawmakers approved a mission in Syria, including sending six Tornado reconnaissance jets, a frigate to help protect a French aircraft carrier, refueling aircraft and 1,200 military personnel.