The main stock index ended 0.12 points weaker at 5,811.76, remaining near its highest close since Dec. 9.
Analysts said the market could 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.
Shares in Ceylon Tobacco Co Plc lost 2.35 percent to 1,123 rupees, while market heavyweight John Keells Holdings gained 0.65 percent to 217.40 rupees.
Foreign investors bought a net 60.5 million rupees worth of shares on Wednesday, extending the net foreign inflows into the bourse to 22.55 billion rupees so far this year.
The day's turnover was 592.6 million rupees ($4.5 million), lower than this year's daily average of 836.7 million rupees.
($1 = 130.8250 Sri Lanka rupees)
(Reporting by Shihar Aneez)
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