SINGAPORE (BLOOMBERG) - Copper fell through US$4,500 for the first time since 2009, while nickel dropped to the lowest level since 2003 and zinc gave up gains made on Friday after Chinese smelters announced plans to cut production.

Copper lost as much as 2 per cent to US$4,486.50 a metric ton, the lowest since May 2009, while nickel dropped 2.5 per cent and zinc declined 2.9 per cent. Smelters in China, which produces more than 40 per cent of the world's zinc, plan to cut refined output by 500,000 tons next year.

"Demand is still the key for commodities at the moment, and supply discipline and production cuts are uncertain," said Helen Lau, analyst at Argonaut Securities in Hong Kong. "There's a chance that local producers will continue to ramp up production and replace the cuts that have been made. Everyone still wants to maintain cash flow at these prices."

The London Metal Exchange index of six industrial metals plunged 4.1 per cent last week to the lowest level since 2009. That was the biggest weekly drop since May.