Swiss watch exports dropped by almost 10% in May led by a slump in shipments to the US, reversing the previous month’s surge when manufacturers were trying to get ahead of a looming trade war.

Total shipments fell 9.5% to 2.1 billion Swiss francs ($2.6 billion), the Federation of the Swiss Watch Industry said in a statement Thursday. Exports to the US, the single-biggest market, were down just over 25%.

The latest data underscore the impact President Donald Trump’s trade policies are having on the watch sector. The US imposed a 10% levy on imports from Switzerland in early April, and has threatened as much as 31% if a new trade deal isn’t reached. The watch industry would be hit hard by any increase.

Shares of Swatch Group AG and Compagnie Financiere Richemont SA fell as much as 2.3% and 2.5% respectively in early trading in Zurich.

Asia continued to suffer, with shipments to China, Japan and Hong Kong all registering double-digit declines in the latest data.

“The rise of ‘luxury fatigue,’ a declining ‘feel-good factor’ from luxury purchases, and worsening consumer sentiment all contribute to a less optimistic outlook,” Vontobel analyst Jean-Philippe Bertschy said in a note.

The Swiss watch industry’s weakness matches a wider trend for the export-dependent country, as overall monthly foreign sales declined 42%, narrowing Switzerland’s trade surplus the most in almost five years.

This story was originally featured on Fortune.com

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