THE reason behind increasing European regulations against ship emissions is unclear, said Washington-based World Shipping Council (WSC) in a letter to the European Parliament.

"What is it about those existing requirements and their consequences for fuel cost and vessel efficiency that are insufficient to ensure dramatic reductions of greenhouse gas emissions from ships?" the council wrote. "What would further regulatory measures accomplish?"

The EU's draft legislation jumps ahead of a game plan that's already in progress at the UN's International Maritime organisation, said the WSC president and CEO Christopher Koch.

The WSC recommends that any EU legislation be deferred until the IMO has finished its work on an initiative for global monitoring, reports American Shipper.

The letter said measures to regulate air emissions are already being discussed in the IMO and that European Parliament's regulatory framework presents a "lack of clarity about what the specific objectives are for further regulatory efforts".

The WSC said legislation requiring monitoring of emissions is "unnecessary" to make decisions about policy actions or regulations concerning emissions.

The ocean emissions demand echoes the path of airline emissions regulations, which were imposed by the EU only to be put on hold while the International Civil Aviation organisation worked out a plan of its own, said the WSC.

The letter questioned the need for additional regulations and repeated its disapproval of unilateral regulation of issues by any nation or group of nations, stressing that action only be taken by the IMO.

"We understand that the Parliament is considering expanding the legislation to address NOx emissions, and perhaps other emissions such as sulphur, PM, BC and methane. We recommend that the legislation not include such an expansion," the letter said.