Copper extends losses, driven by uncertainties over US tariffs

Broader sentiment was also weak as Asian equities fell and oil prices rose more than 2% on renewed Middle East supply concerns, adding to inflation worries ahead of the U.S. Federal Reserve policy meeting this week.

The broader base metal market was mostly under pressure.

Elsewhere on the LME, aluminium CMAL3 rose 0.25%, while zinc CMZN3 fell 0.52%, lead CMPB3 dropped 0.98%, nickel CMNI3 slipped 0.21% and tin CMSN3 lost 1.21%.

On the SHFE, aluminium SAFcv1 fell 0.64%, zinc SZNcv1 dropped 1.94%, lead SPBcv1 declined 2.07%, nickel SNIcv1 lost 1.55% and tin SSNcv1 tumbled 3.81%.

($1 = 6.7066 Chinese yuan renminbi)

Copper sold off sharply on Thursday after Reuters reported that the White House had yet to decide whether to impose tariffs on refined copper imports, as officials weigh higher manufacturing costs against efforts to encourage more domestic supply.

Analysts at Chinese broker Everbright Futures said traders remained focused on the Section 232 tariff decision, which is expected to come on September 28. Shifts in the White House's stance have increased uncertainty over the inventory arbitrage trade, leaving the broker "cautious and bearish" on copper in the near term.

COMEX copper HGc4 lost more than 4% last week, while stocks in COMEX warehouses HG-STX-COMEX declined on Friday for the first time since mid-June, slipping 0.02% from a day earlier to 767,504 short tons, or 696,268 metric tons.

U.S. exchange stocks had risen steadily amid tariff-driven inflows into the country.