Chinese Ministry of Commerce (MOC) on Friday joined other government departments to halt the panic buying of salt prompted by radiation fears over Japan's crippled nuclear power plant, reiterating the country's salt reserves are "quite substantial."

"Salt supply is completely guaranteed in the country," the MOC said in a statement on its website.

China has an annual salt production capacity of more than 80 million tonnes but the country's edible salt consumption is only about 8 million tonnes a year, and salt companies usually have stocks for three months' consumption, said the statement.

The MOC statement was similar to the one issued Thursday by the country's largest salt maker after a wave of panic buying, triggered by rumors that iodized salt could help guard against radiation poisoning.

The company, China National Salt Industry Corp. (China Salt) said it had ample salt reserves to meet the people's needs and panic buying and hoarding was unnecessary.

Most salt sold in China has been iodized as part of government efforts to prevent iodine deficiency disorders.

Rush buying of salt by worried shoppers had emptied supermarket shelves in Zhejiang, Guangdong, Jiangxi, Guizhou, Sichuan, Jiangsu and Hubei provinces as well as the municipalities of Beijing and Chongqing.

The MOC has launched an emergency response mechanism related to daily necessities and ordered local commerce departments to closely monitor the market and organize timely distribution of goods to meet people's needs, according to the statement.

The MOC advised shops and supermarkets to increase their salt inventory if necessary and supply the product in an orderly, balanced and sustained way.

Also, China Salt has launched an emergency response mechanism to step up production and start a 24-hour distribution program.

Rumors in some Chinese cities say that radiation has leaked into the sea from the nuclear power plant in Fukushima, Japan, compromising the safety of salt taken from the sea in the future.

Only 20 percent of the country's salt comes from ocean and most salt on sale is rock salt, which is mined, according to China Salt.

In the equity market, shares of salt-related companies fell early Friday after salt company stocks surged Thursday. Yunnan Salt & Salt Chemical Co., Ltd., dropped more than 4 percent after it rose by the daily limit of 10 percent Thursday.