India's forex reserves dropped by $3.23 billion to $654.86 billion for the week ended December 6, the RBI said on Friday.
In the previous reporting week, the reserves had increased by $1.51 billion to $658.09 billion, ending a multi-week decline in the overall kitty.
The forex reserves had increased to an all-time high of $704.88 billion in end-September.
For the week ended December 6, foreign currency assets, a major component of the reserves, decreased by $3.23 billion to $565.62 billion, the data released on Friday showed.
Expressed in dollar terms, the foreign currency assets include the effect of appreciation or depreciation of non-US units like the euro, pound and yen held in the foreign exchange reserves.
Gold reserves decreased by $43 million to $66.94 billion during the week, the RBI said.
The Special Drawing Rights (SDRs) were up by $25 million to $18.03 billion, the apex bank said.
India's reserve position with the IMF was also up by $12 million to $4.27 billion in the reporting week, the apex bank data showed.