Lufthansa AG and Fraport AG used the opening of a new runway at Frankfurt Airport to plead for a swift return to night flights at Germany's largest airport, arguing they were crucial for the freight industry.

"The price for this runway is very high, too high I could say," Lufthansa Chief Executive Christoph Franz said on Friday at the opening ceremony, referring to the ban on night flights, which was originally proposed in order to get approval for a new terminal and runway at the company's Frankfurt base.

"While we will use the chances offered by this expansion, there is no party atmosphere within my company," he said.

Expanding the airport met with fierce opposition from local residents unhappy at noise levels. Environmental campaigners and airport operator Fraport went along with a mediator's recommendation to ban night flights between 11:00 p.m. and 5:00 a.m.

Although the local government then recommended 17 takeoffs or landings be allowed each night during the 2011/12 winter schedule, a local court imposed a ban from the end of October.

"Freight is a global business and cannot be changed at the last minute," Franz told guests including German Chancellor Angela Merkel, whose government jet was the first to touch down on the new runway.

A handful of protesters with airhorns, whistles and signs stating "No to Airport Expansion" chanted outside the ceremonial marquee situated next to the new runway, while Franz and Merkel gave their speeches.

Fraport CEO Stefan Schulte called on a higher court in Leipzig to make a swift decision on whether to allow the flights again. "No other airport in Germany can take over Frankfurt's role as Germany's economic gateway to the world," he said.

The new runway cost EUR600 million to build and is part of a EUR4.3 billion expansion of the airport first proposed 14 years ago.