Maersk say that despite the financial sweeteners from Singapore's Maritime and Port Authority the company is actually losing money by using low-sulfur fuel that can cost twice as much as ordinary bunker fuel.

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Another is the gritty bunker fuel burned by the many ships in a once-fragrant harbour.

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Scores of oil-covered seabirds have died since an Asian freighter collided with the bay bridge and dumped 58, 000 gallons of thick bunker fuel.

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That means shipowners who wish to ply these waters will have to stop using bunker fuel (the cheap stuff left over once petrol, diesel and aviation fuel have been distilled from crude oil) to power their vessels because burning it produces too much sulphur dioxide, nitrogen oxides and soot.

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New international regulations that require ships to burn low sulfur grades of fuel rather than the comparatively inexpensive bunker fuels most ships currently burn.

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With Bunker C (No. 6) fuel cheap and gigantic containerized shipping available, a manufacturer could make any commodity with high tradability in any location in the world and sell it profitably anywhere else in the world.

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