"But if the United States takes unilateral action without proper multilateral consultations and agreement that could spark big trade disputes, a trade war even," he said.

The WTO’s rules allow them plenty of scope: after two decades of unilateral tariff-cutting most of their tariffs are well below their “bound” rates, the ceilings agreed in the trade club.

Steel-trade protection , an unilateral action , will bring about severe impact on the stability of the WTO.