The most-traded September iron ore contract on China's Dalian Commodity Exchange (DCE) DCIOcv1 traded 0.57% lower at 788.5 yuan ($109.86) a ton.
Talks between top US and Chinese officials in Stockholm, who met on Monday, are expected to continue on Tuesday to resolve longstanding economic disputes between the world's top two economies.
Although the two superpowers have no deep ties in terms of direct trade in steel and its feedstock iron ore, trade frictions could blur demand outlook in top consumer China, said analysts.
Underpinning prices of the key steel feedstock were also falling iron ore arrivals, with those at the major ports slipping by 7.6% week-on-week to 23.2 million tons in the week as of July 27, data from consultancy Mysteel showed.
"Fundamentals of iron ore are relatively healthy amid falling arrivals and resilient hot metal output, supporting prices," analysts at Shengda Futures said in a note.
Markets also awaited details of a Chinese Politburo meeting by July-end that is expected to set the country's economic policy for the rest of the year.
