LONDON - Copper prices hit a record high of more than $14 000 a metric ton on Thursday, as speculators extended their buying spree, encouraged by expectations of strong demand and supported by a weak dollar and geopolitical concerns.

They ignored warnings by some analysts that high prices would chill physical demand by industrial consumers and was not being supported by current supply/demand fundamentals.

Benchmark three-month copper on the London Metal Exchange jumped 9% to an all-time high of $14,268 a metric ton, paring gains to $14 147 by 13:15 GMT.

In LME official open-outcry trading, copper gained 6.6% to $13 950 a ton.

"Copper posted its biggest one-day gain in years... driven by intense speculative trading by bulls in China," Neil Welsh at Britannia Global Markets said in a note.

"Investors are piling into base metals on expectations for stronger US growth and more global spending on data centres, robotics and power infrastructure."

Copper, used in power and construction, is a key metal needed for the energy transition, but global exchange-monitored inventories are at high levels, especially in the US.

The most-active copper contract on the Shanghai Futures Exchange closed daytime trading 6.7% higher at 109 110 yuan ($15 708.77) a ton, after setting a record of 110 970 yuan.

The gains came despite weak spot physical demand in the biggest consumer market China. The Yangshan copper premium, a gauge of Chinese demand for imported copper, declined to $20 a ton on Wednesday, the lowest since July 2024 and down from $55 in December.

Copper is also rising due to a spillover of interest for hard assets, which have sent gold and silver to records, partly due to geopolitical tensions, traders said.

Also supporting metals was a weaker dollar index, which was close to multi-year lows, making commodities priced in the U.S. currency cheaper for buyers using other currencies. 

LME aluminium gained 2.1% in official trading to $3 325.50 a ton, the highest since April 2022, zinc surged 4.4% to $3,513, the strongest since August 2022, lead added 1.6% to $2 049, nickel jumped 3.6% to $18 025 and tin climbed 1.5% to $56 795.