MUMBAI (BLOOMBERG) - The international jewellery business that's part of the empire controlled by Nirav Modi, a billionaire accused of masterminding India's biggest bank fraud, has filed for bankruptcy in the US just as the Indian lender at the heart of the scam revised up its fraud estimate.

Firestar Diamond Inc. blamed liquidity and supply chain challenges and listed up to US$100 million in assets and debt, according to Chapter 11 documents filed Monday (Feb 26) in a bankruptcy court in New York.

Back in India, Punjab National Bank (PNB) told the stock exchanges that the fraudulent transactions could be US$204 million more than the previously estimated US$1.8 billion.

Firestar isn't linked to the complaints filed by authorities, the company said in a Feb 5 email sent through an external spokeswoman. US representatives for the companies didn't respond to a message seeking comment. The Indian banks who've reported exposure to the fraud didn't reply to emails sent Tuesday in Mumbai.

Modi, a jeweller who's dressed actresses including Kate Winslet and Priyanka Chopra, has been accused along with Mehul Choksi of defrauding PNB. PNB alleges that the duo and their associates worked with some rogue PNB employees and used fake guarantees to obtain loans from abroad.

PNB shares fell about 8 percent as of 10:23 am in Mumbai on Tuesday, set for its lowest close since June 2016.

The bankruptcy filing includes Firestar's A. Jaffe Inc. wedding jewellery affiliate and Fantasy Inc. affiliate, and estimates the numbers of creditors at between 50 to 99. The company's diamond operations span the US, Europe, the Middle East and the Far East, according to its website.

The case is Firestar Diamond Inc., 18-10509 US Bankruptcy Court, Southern District of New York (Manhattan).