European Union governments agreed last week to ban single-hulled oil tankers carrying heavy fuel in an attempt to reduce the risk of slicks like that which befouled the coast of northwestern Spain last year.
An exception was made for small vessels serving the Greek islands.
The ban will come into force by July, if it gains quick approval from the European Parliament. It will apply to all vessels using EU ports and to ships flying European flags around the world.
Transport ministers from the 15 EU nations also agreed on a total ban on single-hulled tankers over 23 years old from this year. Prohibition of all single-hulled tankers, whatever their age, will be phased in by 2010. For the largest ships, the ban will start in 2005.
At a request from Greece, an exception will be made for small tankers up to 5,000 tons which are used for transporting fuel to the islands. Their operators will have until 2008 to replace the single-hulled vessels.