Copper prices hit their highest in more than six months on Monday due to worries about availability on the London Metal Exchange, where inventories are at their lowest since February.
Benchmark copper traded up 1.1% at $14,310 a metric ton in official rings from an earlier high at $13,396. Prices of the metal used in the power and construction industries hit an all-time high at $14,527.5 in January.
Stocks in LME-approved warehouses have halved since May to less than 210,000 tons as traders moved copper to the United States ahead of potential tariffs on imports of the refined metal.
Cancelled warrants or metal earmarked for delivery at 50% indicate more copper is due to leave the LME system.
"Although the official data is not yet published, we expect to see record high imports for July. They've been high all year," said Albert Mackenzie, analyst at Benchmark Mineral Intelligence.
However, traders said premiums or backwardations for nearby copper contracts against longer-dated forwards should start to attract metal to the LME.
The premium for cash copper contract over the three-month forward closed at $416.29 on Friday, the highest since November 2021.
The LME's cash copper contract hit a record high $14,830 a ton on Monday.
Deliveries of copper to LME warehouses amounted to 3,700 tons on Friday compared with outflows of 850 tons.
Meanwhile, copper stocks in Comex-registered warehouses at 735,470 short tons or 667,207 metric tons are up nearly 700% since U.S. President Donald Trump mooted import tariffs in February last year.
Elsewhere, copper inventories in warehouses monitored by the Shanghai Futures Exchange have dropped more than 80% since the middle of March to 69,731 tons.
The Yangshan premium , a gauge of China's appetite for importing copper, has slipped to $90 a ton from $115 on July 22, but it is still 350% higher than in January.
Overall, industrial metals were supported by a weaker U.S. currency, which makes dollar-priced commodities cheaper for holders of other currencies.
Aluminium was up 0.5% at $3,270, zinc firmed 0.2% to $3,766, lead was little changed at $1,896, tin added 0.5% to $56,450 and nickel advanced 0.3% to $16,860.
