US officials have accused China of materially retreating last week from commitments made during months of negotiations to end the trade war.
The Chinese Ministry of Commerce said on Tuesday that Vice Premier Liu He went to Washington for two weeks for trade talks, and President Trump's threats to impose new import duties on Chinese goods could call into question the advisability of China's participation in negotiations with the United States.
Rebar prices in Shanghai fell 1 percent to 3,746 yuan (roughly $ 553.34) per tonne. Hot rolled coil is down 1 percent and is listed at RMB 3,706 per tonne.
Traders are also wary of anticipating a decline in demand in the coming weeks amid a slower pace of inventory reduction, CITIC Futures analysts say.
Stocks of steel products held by Chinese traders last week fell by 31,000 tons to 12.41 million tons, according to data provided by consulting company Mysteel.
Demand for steel tends to wane in the summer in China as high temperatures and prolonged rainfall slow down construction work.
The most liquid iron ore futures on the Dalian Commodity Exchange also fell on Wednesday, but prices were able to find some support following Vale's announcement that it will halt operations at the Brucutu mine, a key 30 million tonnes annual capacity iron ore deposit.
Dalian coking coal fell 0.2 percent to RMB 1,367.5 a tonne, while coke rose 1.2 percent to RMB 2,126.5 after a wave of rally in the spot market.