Edible vegetable oils should not be labeled as free of genetically modified ingredients if GM versions don't exist, the State Administration for Market Regulation ordered on Wednesday.

The order aims to regulate the labeling of edible oil and put a stop to misleading labels, the administration said.

Luo Yunbo, a professor of food sciences at China Agricultural University, said the measure is aimed at curtailing misleading practices of some edible oil makers who promote their products by using labels proclaiming that the oil is not genetically modified.

"Some producers mark their products as non-GM only for promotion and unfair competition," he said.

For example, a popular oil product sourced from peanuts is labeled as non-GM, even though there are no GM peanuts anywhere in commercial production at home or abroad.

GM food that has been approved for sale by authorities in China is safe, according to the Ministry of Agriculture and Rural Affairs. Many people in China don't trust GM foods, and such people might be more likely to choose food labeled as non-GM.

China has one of the world's strictest standards for the promotion of GM agricultural products. Only GM cotton and papaya, of all agricultural products, are in commercial production in China, according to the ministry.

Mandatory labeling is required for some major GM products, such as soybeans and corn seeds, as well as their oils.

Zhang Xianwei, a researcher in GM technology at South China Agricultural University in Guangzhou, Guangdong province, said some producers of GM products are reluctant to make that clear on their products because of public mistrust.

The order, which was released on Wednesday, also said producers should clearly label the proportions of all major ingredients of a vegetable oil if it is made of various agricultural products.

The administration also said producers of edible vegetable oils should establish tracking systems to ensure food safety.

Local food safety regulators across China will conduct inspections beginning on Dec 21 that target producers of edible vegetable oils. Violators will be held accountable, it said.