The metal is down by around 18.3 percent from the seven-year high of $2,718 it hit on April 19 in the wake of the announcement of the sanctions, which left the market fearing a supply shortage.

All other base metals were also trading lower, with the dollar near 3-1/2-month highs, making metals more expensive for holders of other currencies.

Barring any further sudden announcements from U.S. President Donald Trump that affect metals markets, "trading price levels should start to return to natural levels, with the logical exception of physical aluminium premiums", Malcolm Freeman, CEO of Kingdom Futures, wrote in a note.

The U.S aluminium premium on Comex was at 21.4 cents per pound ($472 a tonne) on Wednesday, slightly down from a three-year high of 21.5 cents a tonne.

(Reporting by Tom Daly; Editing by Sherry Jacob-Phillips, Gopakumar Warrier and Joseph Radford)