China's COFCO Ltd will return 5.4 tons of genetically modified (GM) corn imported from the United States after forbidden GM ingredients were spotted, the Natioanal Business Daily reported Tuesday citing an official.

"The return of the shipload of corn is in process now, the GM ingredient MON89034 found in the corn is not allowed," the newspaper cited anonymous sources at the Shenzhen Entry-Exit Inspection and Quarantine Bureau.

The corn arrived at Shekou port in Shenzhen in September, and the decision was made in October, sources said.

"The company is negotiating on returning, and the exporter bares the responsibility and the expense of the incident according to the contract," said Zhang Xinyue at COFCO's public relations department.

A spokesman of United States Department of Agriculture said the industry representative is negotiating with Chinese counterparts.

The price gap between the domestic and global markets is believed to be a trigger of corn imports. China used to export corn, but began importing this year, in hopes to level off the price on the domestic market, the newspaper said.

The corn's September 2011 contract closed Monday at 2,278 yuan ($342) per ton on Dalian Commodity Exchange. COFCO imported the shipload of corn at prices below 1,620 yuan per ton, the newspaper said.

China allows 11 varieties of GM corn to be imported among more than 20 in the world.