China is recalling all liquid and powdered milk made before Sept. 14 and Chinese manufacturers must test it for melamine contamination, Chinese government news agency Xinhua reported Tuesday.

It's the first time Beijing has issued a blanket recall of products since the tainted milk scandal broke last month and the latest step China has taken to restore consumer confidence in the quality of Chinese food products.

"Regardless of the brand or the batch, they must be taken off shelves, their sale must be stopped," Xinhua said.

Citing a notice jointly approved by six Chinese government ministries and administrations, the Xinhua report said the products will be sold again only after they pass quality tests and are labelled as safe.

Four babies died in China and tens of thousands of children were sickened after drinking milk tainted with the industrial chemical melamine. Other countries have recalled Chinese-made products over concerns of melamine contamination.

Chinese authorities have blamed dairy suppliers for the crisis, saying they added melamine to watered-down milk to fool quality-control tests and make the product appear rich in protein.

Melamine can cause kidney stones as the body tries to eliminate it and, in extreme cases, lead to life-threatening kidney failure.

The Xinhua report did not say why the recall was being implemented now. Previously, only partial recalls of powdered milk and liquid milk had been issued in China. The country issued a recall Sept. 16 of 69 batches of milk powder made by 22 companies and issued another recall list for liquid milk Sept. 19.

The report does not explain why the cutoff date for the latest notice is Sept. 14, but on Sept. 15 China launched a countrywide inspection of dairy-producing facilities focusing on milk-collecting centres.

The country's chief quality watchdog, the General Administration of Quality Supervision, Inspection and Quarantine, said Monday the latest tests on 172 batches of milk powder from 55 brands showed them to be safe for melamine content.

So far, 1,300 batches of milk powder from 195 brands produced after Sept. 14 have shown no signs of contamination, the watchdog said.

The tainted milk crisis has forced the government to fire local and high-level officials for negligence and to make repeated promises to raise product safety standards.

The State Council, China's cabinet, has also tightened quality-control regulations for the dairy industry, mandating stricter controls over cattle breeding, the purchase of raw milk and the production and sale of dairy products. The measures increase penalties for those caught violating safety standards.

China's Health Ministry issued guidelines last week limiting acceptable melamine levels in milk and food products. There had been no previous standards for the amount of the chemical allowed.

Health officials said deliberate tainting is explicitly forbidden but acknowledged that small amounts of melamine can leach from the environment and packaging into milk and other foods.

With files from the Associated Press