The bank's primary regulator, the Office of the Comptroller of the Currency, has requested reviews of models that measure the possible effects of everything from trading losses to interest-rate moves, the Journal said.

In May, the bank's chief executive, Jamie Dimon, announced the company had lost at least $2 billion through "egregious mistakes" in trading and that the bank had changed its model for measuring so-called value-at-risk in the Chief Investment Office (CIO) where the derivatives portfolio was managed.

The value-at-risk model, which provides an estimate of how much could be lost on average in a single trading day, is one model under scrutiny, the paper said.

JPMorgan officials were not immediately available for comment outside regular U.S. business hours.

The news comes after a person close to the matter said the disastrous derivatives trades may cause the bank's losses to rise to $6 billion in the second quarter, far more than the original estimate of at least $2 billion. Other reports have said the loss could reach $9 billion.

The Securities and Exchange Commission is also investigating disclosures on the value-at-risk measuring model change, the Journal said.

Officials from the SEC and the comptroller's office could not be reached for comment.

(Reporting by Balaji Sridharan and Siddharth Cavale in Bangalore; Editing by Matt Driskill)

• A Permanent Economic Emergency