The country's foreign exchange reserves surged by $3.53 billion to touch a new lifetime high of $404.921 billion in the week to December 22, aided by an increase in foreign currency assets, Reserve Bank data showed on Friday.
In the previous week, foreign exchange reserves had risen by $488.2 million to $401.385 billion.
The reserves had crossed the $400-billion mark for the first time in the first week of September this year but have been fluctuating since then.
Prior to this, it had touched a lifetime high of $402.509 billion on the back of a $1.782 billion surge in the week ending September 15, 2017.
In the current reporting week, the foreign currency reserves, a major component of the overall reserves, rose by $3.773 billion to $380.680 billion.
Expressed in the US dollar terms, the foreign currency assets include the effect of appreciation or depreciation of non-US currencies such as the euro, the pound and the yen held in the reserves.
After remaining unchanged from past many weeks, gold reserves rose by $12.6 million to $20.716 billion.
The special drawing rights with the International Monetary Fund (IMF) rose by $1.8 million to $1.5 billion, the RBI said.
The country's reserve position with the IMF, however, declined by $252.2 million to $2.023 billion, the central bank said.