The BIST banking and holding sector indices declined 0.86 percent and 2.63 percent, respectively.

Among all sector indices, the construction sector index posted the best performance, up 0.66 percent, while the food beverage index saw the worst, down 3.27 percent.

On Tuesday, Borsa Istanbul's BIST 100 closed at 96,274.69, down 3 percent, or 2,978.15 points, with a trade volume of 11.6 billion Turkish liras ($2.5 billion).

The U.S. dollar/Turkish lira exchange rate rose to 4.7260 as of 9.30 a.m. local time (0630GMT) on Wednesday, from 4.6990 at Tuesday's close.

The euro/lira exchange rate stood at 5.5480 in the open market -- from 5.5020 at the previous close -- while one British pound traded for 6.2580 Turkish liras versus 6.2370 at the previous close.

The price of Brent oil decreased to $78.26 per barrel as of 10.00 a.m. local time (0700GMT) Wednesday, from $78.86 at the previous close.