The German government plans to drop a requirement for people to wear masks on flights to and from the country, though the health minister said Tuesday that it could be reimposed if coronavirus cases rise sharply.

The rules mandating masks on flights run through September 23, and the smallest party in the coalition government, the libertarian Free Democratic Party, has pressed for an end to them. The initial draft for this fall’s rules foresaw an obligation to wear N95-type masks on planes as well as long-distance trains and buses.

Health Minister Karl Lauterbach told reporters in Berlin that “next to no masks are worn on international flights — the rules have been loosened there.” He said Germany’s biggest airline, Lufthansa, had said repeatedly that the mandate “can no longer be implemented, so we have refrained from this and are limiting ourselves to the domestic areas where this is possible.”

Lauterbach said that mask-wearing on trains and buses remains “sensible and necessary,” but pointed to better air circulation in planes.

But he said that if COVID-19 cases increase sharply this fall, the government could issue an order reimposing the mask mandate on planes.