Copper markets are awaiting a key U.S. decision on import tariffs as the Commerce Department prepares to deliver a report to the White House that will inform President Trump's next move. If Trump announces tariffs on refined copper effective January 2027, U.S. buyers would likely accelerate imports in the second half of this year to get ahead of the levy. That would drive Comex copper inventories even higher, tighten supplies on the London Metal Exchange and support global prices, Commerzbank analysts say. If tariffs are ruled out, copper could instead flow out of Comex warehouses, providing some relief. In afternoon European trading, copper futures on the LME are up 0.3% to $13,380 a metric ton. (giulia.petroni@wsj.com)