As of this month, Berliners renting out their full apartments on Airbnb can face a fine of up to €100,000 ($115,000), under a new law aimed at curbing a rise in housing prices. The law, called Zweckentfremdungsverbot ("prohibition of improper use"), was passed in 2014 and went into effect on May 1st, the AFP news agency reports. Homeowners can still rent out individual rooms on Airbnb and similar property-listing sites, but renting out entire homes or apartments is now forbidden across the German capital.

Andreas Geisel, Berlin's head of urban development, has said that the law is "a necessary and sensible instrument" to keep housing affordable. Rents in Berlin are still low relative to other European cities, though they increased by 56 percent between 2009 and 2014. Officials say Airbnb and similar sites have helped fuel that rise as more Berliners use their apartments exclusively for short-term rentals, thereby exacerbating the city's housing shortage.

A familiar story

"I am absolutely determined to return such misappropriated apartments to the people of Berlin and to newcomers," Geisel said, as quoted by the AFP.

Airbnb has faced similar accusations in New York and San Francisco, where voters last year rejected a proposition that would have placed some limits on short-term rentals. Some European cities have sought to more tightly regulate the service, with Paris implementing a tourist tax on Airbnb rentals last year.

Berlin has called on residents to anonymously report people who violate the new law. According to The Independent, the number of Berlin listings on Airbnb fell by 40 percent leading up to the May 1st deadline.

"Berliners want clear and simple rules for home sharing, so they can continue to share their own homes with guests," Airbnb Germany said in a statement provided to AFP. "We will continue to encourage Berlin policymakers to listen to their citizens and to follow the example of other big cities such as Paris, London, Amsterdam or Hamburg and create new, clear rules for normal people who are sharing their own homes."