The food and drug authority in northwest China's Gansu province on Thursday told markets to set up special zones for genetically modified (GM) food.

The move guarantees the consumer's right to know what they are buying and choose what they want to buy, according to a circular from the administration.

All food marketers in the province must establish a special counter or shelf for the GM food in their stores from March 1, 2014. They are also ordered post notices in prominent positions to tell consumers they can buy GM food in special zones.

All GM food should clearly indicate contents on their labels, it said.

GM food remains controversial nearly two decades after being introduced to the commercial market, as there is still no consensus on whether it is harmful to humans.

China has a strict trademark mechanism for GM products, including clear labeling, but many transgenetic products remain without such labels.