Komatsu Ltd, the world's second-largest maker of earth-moving equipment, said on Thursday it may build three new plants in China to respond to robust demand for excavators and other construction and mining machinery there.

"We expect continued growth in infrastructure and construction demand in China, and sooner or later our production capacity will hit the limit," said a company spokesman.

The firm is considering building two construction machinery plants and one casting parts factory and has begun talks on buying land for one of the plants, he said.

Japanese business daily Nikkan Kogyo said Komatsu would invest at least five billion yen (US$45.4 million) for construction work on the plants by the financial year starting in April 2009.

It aims to lift its annual production capacity for hydraulic excavators in China to at least 16,000 units by the 2010/11 business year, up 33 percent from that planned for the current year, the paper said.

China's rapid urbanisation and big infrastructure projects have meant soaring demand for construction machinery, and its hunger for minerals has spurred a massive upturn for the global mining industry.

In China, mainly an excavator market, Komatsu has 18 percent of the crawler excavator segment, ahead of Hitachi Construction Machinery Co Ltd, Doosan Infracore Co Ltd and Hyundai Heavy Industries Co Ltd, according to private research firm Off-Highway Research. Industry leader Caterpillar Inc ranks fifth with 10 percent.