Sri Lanka stx at 3-wk low on interest rate concerns

COLOMBO, July 5 (Reuters) - Sri Lanka's stock market edged down for a third straight session on Thursday as investors sold shares on growing concerns of rising interest rates.

The rupee ended a tad weaker in dull trade.

The Colombo Stock Exchange's main index fell 0.44 percent or 21.97 points to 4,924.61, its lowest since June 14.

"There is no buying power due to lack of liquidity as the interest rates are rising," said a stock broker on condition of anonymity.

The rupee closed flat at 133.75/85 to the dollar, edging down from Wednesday's close of 133.70/80.

Dealers said though the depreciation pressure on the local currency has slightly eased on exporter demand, heavy oil bills may threaten the stability of the rupee.

Sri Lanka's central bank has taken several stringent policy measures this year aimed at cutting imports, including raising policy rates and restricting credit growth, though a prolonged drought has increased oil imports for thermal power.

The rupee has lost 17.5 percent since November, when the government allowed a 3 percent devaluation. The sharp fall drove the annual inflation rate to a 41-month high in June, data showed on Friday. ($1 = 133.8000 Sri Lanka rupees) (Reporting by Ranga Sirilal and Shihar Aneez; Editing by Jeremy Laurence)