Vietnam's trade surplus with the U.S. expanded sharply in May as exports swelled and its imports from China also jumped, exacerbating sore points with Washington that could hurt Hanoi's efforts to avoid crippling tariffs. Separate trade data from the U.S. also showed Vietnam's surplus overtook Mexico's in April, lagging only China and the European Union. U.S. President Donald Trump has vowed to bring down the U.S. trade deficit and the Southeast Asian country faces one of his highest "reciprocal" tariffs at 46% if a deal cannot be negotiated before a pause on the levies ends in early July.