Copper prices edged up on Thursday on growing optimism over progress in U.S. trade talks, although uncertainty around copper import tariffs kept traders cautious.

Three-month copper on the London Metal Exchange inched up 0.14% to $9,944 a ton by 0700 GMT. The most-traded copper contract on the Shanghai Futures Exchange was up 0.1% at 79,890 yuan ($11,171.08) a ton.

The European Union and the U.S. are moving toward a trade deal that could include a 15% U.S. baseline tariff on EU goods and possible exemptions, two European diplomats said on Wednesday. The deal would follow President Donald Trump’s recently announced agreement with Japan.

As for copper, Chile’s mining minister and the chairman of Codelco, the world’s biggest copper producer, said on Wednesday that they have not yet received details on 50% copper tariffs, due to be imposed by the U.S. on August 1.

“The deadline of August 1 is approaching, but no one knows which copper products will be affected,” a Shanghai-based metals analyst at a futures company said, adding this makes it hard to predict where copper prices will go in future.

On Thursday, SHFE aluminium fell 0.41% to 20,760 yuan a ton, lead ticked down 0.09% at 16,890 yuan, zinc gained 0.48% to 23,015 yuan, and nickel gained 0.66% to 124,360 yuan.

SHFE tin jumped 1.88% to 273,950 yuan, after touching 275,750 yuan earlier in the session, the highest since April 7, mainly due to persistently low inventories especially out of China.

LME aluminium eased 0.21% to $2,645.5 a ton, while zinc inched up 0.47% to $2,875.5, tin was up 0.41% at $34,995, nickel nudged up 0.21% at $15,605, and lead traded higher by 0.17% at $2,035.5.
Source: Reuters