The main stock index dropped 0.16 percent, or 9.64 points, to 5,857.36. On Thursday, it had closed at its highest level since Nov. 7.
Shares in Aitken Spence fell 6.12 percent to 95.10 rupees.
Foreign investors sold a net 300.4 million rupees ($2.30 million) worth of shares on Thursday, but the bourse has witnessed a net foreign inflows of 22.25 billion rupees so far this year.
Analysts expect the market to witness a rally in the near future as the possibility of retail investors returning to risky assets is increasing due to falling interest rates.
Yields in 91-day and 182-day treasury bills dropped 12 basis points and 29 bps, respectively, at a weekly auction on Wednesday, while 364-day T-bill yield fell 62 bps. All T-bill yields fell to more than two-year lows.
The day's turnover was 1.06 billion rupees, higher than this year's daily average of 836.5 million rupees.
($1 = 130.7500 Sri Lanka rupees)
(Reporting by Shihar Aneez; Editing by Subhranshu Sahu)
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