India is planning to ask state-owned lender Punjab National Bank to compensate other lenders for losses arising out of the $1.8 billion fraud allegedly perpetrated by jewelers Nirav Modi and Mehul Choksi, a person familiar with the matter said. Banks including Allahabad Bank, Axis Bank and UCO Bank were hit after the jewelers allegedly colluded with a rogue PNB employee to obtain fraudulent guarantees for loans from their overseas branches. The quantum of loss isn\u2019t known as the lenders are still in the process of investigating the fraudulent transactions, the person said, asking not to be identified as the discussions are private. The extent of the fraud is becoming clearer as more lenders disclose exposure to the illegal transactions. PNB said last week it detected the fraud at a single branch in Mumbai. All transactions found valid will have to be honored by PNB and if the investigators find a fault with the paying bank then the amount will be apportioned accordingly, the person said. Shares of PNB erased gains to fall as much as 2 percent before ending the day with a loss of 1.1 percent, compared with a 1 percent advance for the benchmark S&P BSE Sensex index.The lender didn\u2019t immediately respond to an email seeking comment and Finance Ministry spokesman D.S. Malik didn\u2019t answer calls to his mobile phone The finance ministry has also asked all state-run lenders to review their systems and certify there are no loopholes, the person said. Banks are also reviewing their accounts overseas for any rogue transactions. The government doesn\u2019t plan to inject more money in banks, including in PNB, beyond what has been allocated. The New Delhi-based lender will get a capital boost from an expected sale of delinquent Bhushan Steel Ltd. and putting on block its non-core assets.