The main share index closed 0.03 percent, or 1.62 points weaker, at 5,746.09, slipping from its highest close since Oct. 10.
The index has risen 4.19 percent in the seven sessions through Friday due to declining yields in government securities after the central bank cut its key policy rates last month.
Turnover was 557.5 million rupees ($4.38 million). Foreign investors were net buyers of 199.8 million rupees worth of shares after being net buyers of a record 38.63 billion rupees worth shares last year.
The rupee closed slightly weaker at 127.35/40 to the dollar from Friday's close of 127.30/40 in dull trade, dealers said. ($1 = 127.4000 Sri Lanka rupees)
(Reporting by Ranga Sirilal and Shihar Aneez; Editing by Ron Popeski)
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