Germany is extending a warning against worldwide travel until June 14 as curbs remain in place in many countries to stem the coronavirus pandemic, Foreign Minister Heiko Maas said Wednesday.

"We have not yet reached the point where we can recommend carefree travel," Maas said. "Therefore it is necessary to extend the worldwide travel warning until mid-June".

Europe's biggest economy has brought home 240,000 stranded tourists in the last four weeks, Maas said, adding, "we're not going to undertake such an action again in the coming summer".

"We still have a situation where there are entry and exit restrictions in many countries, and international air traffic is grounded," he said.

Germany would continue to discuss the situation with European partners during this time, he added. "It will take weeks before things return to normal both here and in other countries. Therefore we do not assume that it is responsible to travel worldwide in the next few weeks, at least until June 14."

Germany has closed its land borders and the European Union has also sealed external borders to incoming travellers to try to slow the spread of the novel coronavirus. The government in March agreed to spend 50 million euros ($56 million) in a deal with commercial airlines to fly citizens home from affected regions.

Maas had already dampened German expectations of summer holidays in an interview with the Bild am Sonntag newspaper at the weekend. "We have already experienced what an infection cluster in a popular holiday destination can do," he added, referring to a chain of infections that began in the Austrian ski resort of Ischgl.

Germany's Robert Koch Institute disease control authority on Wednesday reported over 157,000 confirmed coronavirus infections.