Benchmark copper on the London Metal Exchange ended down 0.2pc at $5,892 a tonne.
"The resolution, or otherwise, of the trade talks between the United States and China are of meaningful importance to base metals markets," said Guy Wolf, head of market analytics at Marex Spectron.
"Underlying physical markets are significantly more robust than the headlines would suggest they have any right to be. That is not to suggest things are booming, nor are they looking as tight as they perhaps were earlier in the year."
REVERSAL: Traders said a break of the 21-day moving average at $5,925 triggered stop levels, which earlier in the session took prices to a session high at $5,946.50.
Reinforcing this was a drop in copper stocks <MCUSTX-TOTAL> in LME warehouses, which fell 4,675 tonnes to 298,300 tonnes.
Funds and dealers trading headline stocks had taken bets on lower prices after LME copper inventories last week rose above 300,000 tonnes from 239,925 tonnes.
TRADE: The United States and China agreed late in June to restart trade talks after President Donald Trump offered concessions including no new tariffs and an easing of restrictions on tech company Huawei.
The Trump administration has accused China of engaging in unfair trade practices that discriminate against US firms, forced technology transfers and intellectual property rights theft, all charges Beijing has denied.
CHINA: Chinese industry accounts for about half of global consumption of industrial metals. Markets are looking ahead to China data on bank loans.
New bank loans in China are expected to have picked up to a five-month high in June, a Reuters poll showed, as Beijing kept ample liquidity in the financial system to support the slowing economy.
DOLLAR: A higher US currency makes dollar-denominated metals more expensive for importers in other currencies, which potentially could subdue demand.
ZINC: Prices of the metal used to galvanise steel have recently come under pressure from expectations of rising supply and the likelihood of a second half balanced market or surplus.
Zinc was down 1.2pc at $2,378 a tonne, a six-month low.
Receding worries about zinc shortages on the LME market can also be seen in the discount for the cash over the three-month contract, which is around $2.60 a tonne, against a premium of more than $160 a tonne late May.
PRICES: Aluminium gained 0.3pc to $1,809, lead gained 0.8pc to $1,884, tin added 0.7pc to $18,490 and nickel was up 1.9pc to $12,720 a tonne.