BEIJING (Reuters) - The United States hopes that more varieties of its genetically modified corn will be approved for import by Beijing, the U.S. ambassador to China said on Wednesday.

The comments came after the world’s top grains buyer this month approved two new strains of U.S. genetically modified (GMO) crops for import, from Dow AgroSciences and Monsanto.

“We are hopeful that other ... corn traits can also be approved,” said Terry Branstad, who arrived in Beijing on Tuesday to take up his post.

China does not permit the planting of genetically modified food crops, but does allow some GMO imports for use in animal feed.

But getting a new GMO crop variety approved for import typically takes around six years, compared with under three in other major markets, forcing leading agrichemical players to restrict sales during China’s review process.

This month’s approvals of new GMO imports follow an agreement by the two nations in May to restart trade in U.S. beef.

“We are excited about the trade expansion and the opportunity to ... market American beef here,” Branstad said.