Turkey's stock exchange dropped 0.45 percent, or 420.09 points, to open at 92,272.08 points Thursday.
The banking and holding sector indices fell 0.76 percent and 0.40 percent, respectively.
Among all sector indices, the leasing factoring sector index posted the best performance, up 1.02 percent, while the textile-leather sector was the worst, down 1.01 percent.
On Wednesday, Borsa Istanbul's BIST 100 closed at 92,692.17, down 0.83 percent or 776.82 points, with a trading volume of 5.6 billion liras ($984 million).
The USD/TRY exchange rate increased to 5.7250 as of 9.30 a.m. local time (0630GMT) on Thursday. It was 5.6950 at Wednesday's close.
The euro/lira exchange rate also rose to 6.5510 by market open -- from 6.5030 at the previous close -- and one British pound traded for 7.4090 Turkish liras over 7.3820 at the previous close.
The price of Brent oil dropped to $75.56 per barrel as of 10.00 a.m. local time (0700GMT) Thursday. It was $76.47 on Wednesday.