The 11-mile tunnel will run across a strait in the western Baltic, linking the German island of Fehmarn with the Danish territory of Lolland, greatly reducing journey times between central Europe and Scandinavia when it opens in 2029. The 31-mile Channel tunnel, completed in 1993, was made using five boring machines.

On the Danish side, work has already begun on the project. Yet German firms have been lagging behind as court cases have prevented them from starting construction. Ferry firms which stand to lose a great deal of revenue after the tunnel’s completion and environmentalists have been lodging complaints at the Leipzig Federal Administrative Court, which have, however, all been rejected, giving the German side the opportunity to begin work.

Numerous complaints are still lodged at the European Court of Justice but those are not expected to damage the project’s prospects as it aims to wrap up construction by 2029.

Femern A/S CEO Claus F. Baunkjær said: “We are pleased that the German regulatory approval of the Fehmarnbelt project has now received clarification. It is a historic milestone that has now been achieved.

“Construction of the Fehmarnbelt tunnel has already begun on the Danish side. Now we can begin on the German side as well. We would like to thank our German and Danish partners for their efforts.”