Oct 15 (Reuters) - The Baltic Exchange's dry bulk sea freight index, which monitors rates for vessels moving dry bulk commodities, extended losses for a second day on Wednesday, pressured by weakness in larger capesize vessel rates.

* The main index .BADI, which factors in rates for capesize, panamax and supramax shipping vessels, fell 25 points, or 1.2%, to 1,997 points.

* The index had posted its worst day in two-weeks on Tuesday.

* The capesize index .BACI fell 91 points, or 3%, to 2,916 points.

* Average daily earnings for capesize vessels .BATCA, which typically transport 150,000-ton cargoes such as iron ore and coal, decreased by $753 to $24,185.

* Iron ore futures fell for a second straight session, driven by concerns over the demand outlook stemming from a worsening Sino-U.S. trade spat and rising steel stocks in top consumer China. IRONORE/

* The U.S. and China on Tuesday began charging additional port fees on ocean shipping firms that move everything from holiday toys to crude oil, making the high seas a key front in the trade war between the world's two largest economies.

* "This development is expected to influence trade flows, potentially raise operational costs, and inject additional volatility into freight sentiment," said Nikos Tagoulis, senior analyst at Intermodal in a weekly note.

* "The avoidance of Chinese cargoes by U.S.-linked vessels is likely to tighten effective tonnage availability, providing sustained support to freight rates rather than a purely temporary spike," said Tagoulis.

* The panamax index .BPNI rose 0.3% to 1,821 points.

* Average daily earnings for panamax vessels .BPWT, which usually carry 60,000-70,000 tons of coal or grain, rose by $49 to $16,386.

* Among smaller vessels, the supramax index .BSIS rose 0.7% to 1,418 points.

(Reporting by John Biju in Bengaluru; Editing by Tasim Zahid)

((John.Biju@thomsonreuters.com;))