LONDON: Copper prices extended their decline to a one-month low on Tuesday on renewed fears that troubles at China's debt-laden Evergrande Group could seep into the global economy.

Three-month copper on the London Metal Exchange had slipped 0.3pc to $8,983 a tonne by 1555 GMT, its lowest since Aug. 19. The contract has lost about 7pc this month.

"There's a general worry about the strength of the global economy," said Ole Hansen, head of commodity strategy at Saxo Bank in Copenhagen. "The market is trading on the nervous side ahead of that Chinese announcement from Evergrande on Thursday."

Evergrande is due to pay $83.5 million in bond interest on Thursday.

"The break of copper's $9,000 psychological level is forcing some renewed liquidation by disappointed longs who tried to buy the dip," Hansen added, referring to a rebound during morning trading.

LME copper may test support at $9,056

Investors were also on alert for a faster pace of stimulus tightening in the United States; as central bank officials there entered a two-day meeting that is due to conclude on Wednesday.

Chinese markets are closed for a holiday and will reopen on Wednesday.

Canadian miner Teck Resources Ltd cut its forecast for annual refined zinc production due to wildfires in British Columbia.

The global world refined copper market showed a deficit of 90,000 tonnes in June, compared with a surplus of 4,000 tonnes in the prior month, data showed.

Europe's largest copper producer, Aurubis AG, said its Stolberg copper products plant in Germany would start resuming some production on Nov. 1.

LME aluminium shed 0.4pc to $2,851 a tonne, nickel dropped 1.4pc to $18,795, zinc shed 0.7pc to $2,993, lead fell 0.8pc to $2,139 and tin added 0.1pc to $33,950.