This, she said, would represent a drop of nearly 4 percentage points from the WTO's previous projection.
Okonjo-Iweala said the US tariff measures would "have substantial implications for global trade and economic growth prospects".
She urged WTO members to responsibly manage the tensions resulting from the US measures.
Meanwhile, International Monetary Fund (IMF) managing director Kristalina Georgieva said “they clearly represent a significant risk to the global outlook at a time of sluggish growth”.
“It is important to avoid steps that could further harm the world economy. We appeal to the United States and its trading partners to work constructively to resolve trade tensions and reduce uncertainty,” Georgieva said in a statement.
President Donald Trump slapped 10-per cent import duties on all nations and far higher levies on imports from dozens of countries.
Despite the US measures, the vast majority of global trade still flows under WTO's ‘most favoured nation’ (MFN) status, which bars countries from discriminating between their trading partners, Okonjo-Iweala said.
"Our estimates now indicate that this share currently stands at 74 per cent, down from around 80 per cent at the beginning of the year," she was quoted as saying by global media reports.
"WTO members must stand together to safeguard these gains," she added.
ALCHEMPro News Desk (DS)
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