China has sent a notice to the World Health Organisation defending its food safety standards and sentenced another food and drug watchdog official for bribery, its latest moves to assure the world its exports are up to par.

A series of scandals involving sub-standard Chinese exports ranging from pet food and toothpaste to toys has put increasing pressure on Beijing to clean up its manufacturing sector.

The notice, posted on the Health Ministry's Web site (www.moh.gov.cn) on Wednesday but sent one week ago, said China was willing to cooperate globally to tackle the problem.

The Chinese government is willing to increase information exchange and communication with international society and other countries in line with its attitude of openness and transparency, it said.

The notice detailed the actions and laws China has adopted to ensure food safety, explained the roles of the various watchdog bodies and promised to strike hard against illegal behavior by companies.

In its latest move to crack down on lax official enforcement, a court sentenced Zheng Shangjin, former head of the food and drug safety watchdog in the eastern coastal province of Zhejiang, to four years in prison for taking bribes and abuse of power, the official Xinhua news agency reported.

The court showed leniency in the sentence because Zheng surrendered to police and the 680,000 yuan ($90,000) he had accepted in bribes was recovered, the report said.

The sentencing follows the execution in July of Zheng Xiaoyu, former head of the national food and drug safety watchdog, for corruption.

On Tuesday, an appeals court in Beijing upheld the suspended death sentence for Cao Wenzhuang, former head of the drug registration department under the State Food and Drug Administration, the Southern Metropolis Daily said.

Cao, who worked under Zheng Xiaoyu for years and was once his secretary, was convicted of dereliction of duty and taking bribes worth over 2.4 million yuan from pharmaceutical companies.

The Health Ministry notice said the quality of farm products was already greatly increasing.

At present, more than 94 percent of vegetables meet chemical residue standards, the notice said.

A spokeswoman for the WHO in Beijing said though it had not requested the Health Ministry's report, it welcomed it.

While there's nothing specifically new in it, it does show that China has recognized it has a challenge and is working to address it, said spokeswoman Joanna Brent. We're pretty positive about that.