Chicago Board of Trade soyabean futures rose on Wednesday as Iran and the United States signaled a deescalation of tensions after an Iranian missile attack against US forces in Iraq.

Traders also spent the day squaring their positions ahead of a key US Department of Agriculture (USDA) crop report, due at the end of the week.

Analysts polled by Reuters expect the agency to trim its US soyabean crop estimate, tighten its end-of-season stocks outlook and minimally adjust its South American crop views.

Investors also are awaiting details of the US-China Phase 1 trade deal due to be signed next week. The deal is expected to boost US soyabean sales to China.

Brazil could lose some gains it made in the global soya market during the US-China trade war in the event that the two countries close a deal ending the dispute, a Brazilian Agriculture Ministry official said on Wednesday.

The US Department of Agriculture said its weekly export sales report will be issued on Friday, a day later than normal, due to a winter storm in Washington that prompted an early closure of federal agencies on Tuesday, the agency said on its website.