"The amount involved in frauds that occurred between 2000-01 and 2017-18 formed 90.6 per cent of those reported in 2018-19," the central bank said in its Financial Stability Report (FSR).
Giving further insight on the data, the RBI said that the systemic and comprehensive checking of legacy stock of NPAs of public sector banks (PSBs) for fraud during 2018-19 has helped unearth frauds perpetrated over a number of years.
"..and this is getting reflected in increased number of reported incidents of frauds in recent years compared to previous years," it added.
The RBI said that the recognition of date of occurrence is not uniform across banks and to ensure timely and assured detection of frauds in large accounts, the government issued a direction in February 2018 to all PSBs to examine all NPA accounts exceeding Rs 0.5 billion from the angle of possible fraud.
The FSR reflects the collective assessment of the Sub-Committee of the Financial Stability and Development Council (FSDC) on risks to financial stability, as also the resilience of the financial system. The June 2019 report also discusses issues relating to development and regulation of the financial sector.
In its report, the RBI has also highlighted the need for greater surveillance of large entities among the non-banking finance companies (NBFCs) and housing finance companies (HFCs) as their failure could have contagion affect, putting the entire sector into crisis.
The recent development in the case of IL&FS and other NBFCs leading to a liquidity crisis like situation has prompted the RBI to respond.
The failure of a large HFC could erode 5.8 percent of the total Tier-I capital of the banking system, while that of a large NBFC could lead to loss of 2.7 percent of the Tier-I capital and a failure of one bank.
On the whole, the apex bank said that India's financial system remains stable while the resilience of banking sector has improved. The global geopolitical environment, however, poses challenges, it said.
Reviving private investment demand remains a key challenge going forward while being vigilant about the spillover from global financial markets, the report said.
( With inputs from IANS )