The move would give US rice farmers access to the world's biggest rice consumer, with China importing about 5 million tonnes last year, Perdue said in a statement.

"We waited a decade for the protocol to be signed and our members are anxious to meet the demand of China's consumers for safe, high-quality US rice," USA Rice President Betsy Ward said in a press release, adding that China consumes the equivalent of the entire US rice crop every 13 days.