Total reserves had declined by USD 2.64 billion to USD 415.05 billion in the previous reporting week.
The reserves had touched a record high of USD 426.028 billion in the week to April 13. It had crossed the USD 400-billion mark for the first time in the week to September 8 last year, but has since been fluctuating.
The core currency assets fell by USD 2.229 billion to USD 387.597 billion for the reporting week, the apex bank said.
Expressed in US dollar terms, the foreign currency assets include the effect of appreciation or depreciation of the non-US currencies such as the euro, the pound and the yen held in the reserves.
The value of the gold assets was unchanged at USD 21.70 billion, it said.
India's special drawing rights declined USD 2.9 million to USD 1.498 billion during the reporting week, while the reserve position in the IMF was down USD 3.9 million to USD 2.027 billion, the central bank said.