China has overtaken the United States for the first time to become the world's largest smartphone market by volume, sina.com reported Wednesday.

Smartphone shipments reached 24 million units in China during the third quarter of 2011, up by 58 percent from the second quarter, while smartphone shipments reached just 23 million units in the US, down by 7 percent.

China's rapid growth has been driven by aggressive subsidizing by operators of high-end models like the Apple iPhone, and emerging of low-cost Android models from Chinese brands such as ZTE.

But China may not lead for long. Demand for smartphones in the US fell because people were expecting the unveiling of the new iPhone, resulting in China's narrow lead. The US is expected to take back the top spot in the fourth quarter, according to Strategy Analytics.

Nokia currently leads China's smartphone market, with a 28 percent share, followed by Samsung with 18 percent, while HTC leads the United States smartphone market, with a 24 percent share, followed by Apple, with 20.6 percent.