LONDON: Copper prices retreated further from an 11-month peak on Wednesday, on worries about demand in top metals consumer China while lead slumped after a sharp rise in inventories.

Three month copper on the London Metal Exchange (LME) was down 0.8% at $8,902 a metric ton by 1050 GMT after falling by 1.2% in the previous session. Copper prices spiked to a peak of $9,025.50 a ton on Monday, the highest since April last year, after a rare agreement by China’s copper smelters last week to cut output.

But investors are worried about China’s troubled and debt-laden property sector, which is usually a key consumer of industrial metals. “There’s not much real demand and they haven’t really addressed the property sector yet, so that’s weighing on the market,” Robert Montefusco at broker Sucden Financial said.

Lead dropped 1.2% to $2,068 a ton after LME inventories soared by 67,350 tons or 34% to the highest since March 2013, highlighting excess supply in the market.

Macquarie expects a surplus in the global lead market of 76,000 tons this year and 138,000 tons in 2025. Montefusco said investors were buying options with a strike price of $2,000, hoping to benefit from further losses. In Shanghai, nickel and tin prices declined as investors eyed more mining output from main producer Indonesia after the country said it will accelerate its approval process. A senior Indonesian mining ministry official said the country had issued production quotas of 152.62 million tons of nickel ore and 44,481.63 tons of tin so far this year, and was working to accelerate the approval process.

The delayed issuance had sparked fears of supply tightness, supporting prices over the past few months. On the LME, nickel edged up 0.3% to $17,455, aluminium added 0.4% to $2,279, zinc dipped 0.2% to $2,502, and tin shed 1.3% to $27,085.