Komatsu Ltd. said sales in China are exceeding its forecasts, as Beijing's $585 billion stimulus plan fuels demand.

Industrywide sales of excavators in China fell by 15 percent in April from a year earlier and showed break-even growth in May, slightly better than Komatsu was expecting, Taizo Kayata, senior executive officer in charge of Komatsu's China operations, said Thursday in Tokyo.

"The impact of China's infrastructure construction has been gradually emerging in May and June," Kayata said. "We expected our sales in China to be slightly negative this quarter, but now it looks like sales will be about flat."

Komatsu, the world's second-largest construction machinery maker, and its rivals, including U.S.-based Caterpillar Inc., are counting on China's plans to build railways and roads as part of a 4 trillion yuan stimulus package to boost demand.