The reserves had increased by USD 205.8 million to USD 278.80 billion for the week ended Aug 16.
The foreign currency assets (FCA) - the biggest component of the forex reserves - fell by USD 1.07 billion to USD 250.48 billion, the weekly statistical supplement of the central bank showed.
The FCA had grown by USD 211.7 million at USD 251.56 billion in the previous week.
The central bank said FCA in US dollar terms included the effect of appreciation or depreciation of non-US currencies held in reserve, such as the pound sterling, euro and yen.
Gold reserves remained stagnant at USD 20.74 billion. The reserves of the precious metal remained stagnant after plunging USD 1.28 billion in the week ended July 5.
The special drawing rights (SDRs) declined by USD 4.5 million to USD 4.38 billion during the week ended Aug 23, while reserves with the International Monetary Fund (IMF) went down by USD 2.2 million to USD 2.10 billion.
The SDRs had declined by USD 3.9 million to USD 4.39 billion during the previous week, while reserves with the IMF were down by USD 2.00 million to USD 2.10 billion.
--IANS (Posted on 31-08-2013)