The main share index fell 1.19 percent, or 67.38 points, to close at 5,605.26, its lowest close since Dec. 26. It has fallen 3.9 percent over the last six sessions due to concerns over the rupee which hit a record low on Aug. 28.
'The market is lacklustre. There is no direction. The rupee depreciation is also a concern,' a stockbroker said.
The rupee traded steady on Monday, supported by an earlier directive by the central bank not to trade the currency beyond a certain level, but it still remained under pressure, dealers said.
Speaking at a roadshow in Hong Kong, the central bank Governor Ajith Nivard Cabraal said the slight adjustment in the rupee was 'due to the fact that there were many trading partners of Sri Lanka which have had major changes in their currencies'.
The bourse is in oversold territory, with the 14-day Relative Strength Index on Monday at 25.338, below its lower neutral level of 30, Thomson Reuters data showed.
Shares in Ceylon Tobacco Co PLC fell 7.73 percent to 1,030.30 rupees, while top conglomerate John Keells Holdings Plc lost 1.43 percent to 206.40 rupees.
Monday's turnover was 323.7 million rupees ($2.43 million), way below this year's daily average of about 886.2 million rupees.
Foreign investors were net buyers of 107.2 million rupees worth of shares, snapping three straight sessions of outflows, and extending net foreign inflows in stocks to 18.61 billion rupees so far this year.
($1 = 133.0250 Sri Lanka rupees)
(Reporting by Ranga Sirilal and Shihar Aneez; Editing by Prateek Chatterjee)
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