China, the world’s biggest buyer of soybeans, has yet to book any US soybean cargoes from its autumn harvest, traders have said, opting for South American supply instead.

US farmers stand to miss out on billions of dollars of soybean sales because of unresolved trade tensions that have halted exports to China.

Senior Chinese trade negotiator Li Chenggang on Monday met political and business leaders from the US Midwest, where the bulk of American soybeans are harvested, signalling that the world’s second-largest economy could purchase some American soybeans ahead of more wide-ranging trade talks.

However, disagreement on technical details appears to be complicating negotiations, with Chinese and US trade officials set to meet again at the US Treasury on Thursday.

“Regarding the trade of soybeans, the United States should take positive action to cancel the relevant unreasonable tariffs to create conditions for expanding bilateral trade,” commerce ministry spokesperson He Yadong told a news conference.