Montreal: The World Anti-Doping Agency suspended the accreditation of China's national anti-doping laboratory on Thursday, just months out from the Olympics and weeks after a drugs controversy in Chinese swimming.

The suspension for a maximum of four months means China's National Anti-Doping Laboratory is barred from carrying out WADA-related tests such as blood and urine analysis. "During the period of suspension, samples are required to be transported securely to another WADA-accredited laboratory," Montreal-based WADA said in a statement. China has become a leading Olympic power, topping the medals table at the Beijing 2008 Games and finishing second behind the United States in 2004 and 2012.