So sensitive is America on this issue that when the WTO ruled in May that the US ban on shrimp imports on environmental grounds was illegal, America asked for the report to be kept under wraps until after the second ministerial meeting of the WTO, which coincided with the 50th anniversary celebrations of the GATT (General Agreement on Tariffs and Trade) system.

Washington subsequently appealed against the ruling and the matter has yet to be decided finally.

The WTO ruling was in response to a complaint by India, Pakistan and Thailand whose shrimp exports are banned because the US says they do not protect their turtle population by installing turtle-extruder devices in fishing vessels.

Now this row has become linked to a very important item on America's legislative agenda: giving the American president a free hand in negotiating trade deals, the so-called fast-track negotiating authority.

Bill Clinton had failed to have his fast-track trade negotiating authority renewed last year. This has hamstrung him so much that America's agenda of liberalising trade worldwide has virtually ground to a halt.

Now, eight environmental groups have written to Republicans in the American Congress, urging them to again deny this authority to the President. The Bill for fast-track authority comes up for voting in the House of Representatives late next month.

The environmental groups, with a membership of seven million, have written to Republican senators that world trade rules have already undermined important environmental and public-health laws in areas such as the protection of endangered species and forests, and controlling pollution.

The shrimps case has been specifically cited. The letter says that "In an unprecedented display of arbitrary power,'' the WTO panel ruled against the US ban. It asserts that this sets a ``dangerous precedent that could permanently subordinate global environmental protection to trade promotion''.

The developing countries have had an uphill task in recent years in trying to keep the rich world from imposing its stiff environmental standards on their exports, saying that these constitute a non-tariff barrier to trade considered undesirable by the WTO regime.

An adverse ruling for the US by the appellate panel in the shrimp-turtle case could make this a test case for America's commitment to the WTO regime. It is often said that American resistance to a WTO ruling, which is legally binding on members, could seriously undermine the world trade regime that has seen such success in recent years.