They want unmanned aircraft with emissionsensors to catch owners trying to save money by using dirtier fuel.

Maersk Line and 10 other owners will formthe Trident Alliance to fight for “robust enforcement” of the rules, Bloombergreported.

From 2015 levels of sulphur in bunkers mustbe cut by 90% in European emission control areas (ECAs).

Smaller companies may find it cheaper topay fines, which will be EUR 50,000 ($68,000) in Germany, for example.