Chinese ride-hailing giant Didi Chuxing is being probed by the country's market watchdog, according to a Reuters report.

The State Administration for Market Regulation (SAMR), is said to be investigating whether Didi has been unfairly squeezing out smaller rivals.

It comes as Didi readies for what could be this year's biggest US market debut.

Beijing has been increasingly reigning in China's tech giants, including Alibaba and Tencent.

The SAMR is also examining whether the pricing mechanism used by the firm's core ride-hailing business is transparent enough, said Reuters quoting people familiar with the matter.

The SAMR has not yet responded to requests for comment from the BBC.