Last week, the reserves had risen by $43.3 million to $319.39 billion, after falling for two consecutive weeks.
Foreign currency assets (FCAs), a major constituent of overall reserves, dipped by $783 million to $291.318 billion for the week ended August 22, the Reserve Bank of India said in its weekly statement.
FCAs, expressed in dollar terms, include the effect of appreciation/depreciation of the non-US currencies such as the euro, pound and yen held in reserves.
Gold reserves remained unchanged at $21.173 billion in the reporting week.
The special drawing rights were down $19.8 million to $4.396 billion, and India's reserve position with the IMF also dropped $7.9 million to $ 1.691 billion during the week, the RBI data showed.