Efforts by banks including HSBC Holdings Plc and ABN Amro Bank NV to recover US$3.5 billion ($4.76 billion) from a collapsed oil trader in Singapore have hit a snag over attempts by a court-appointed manager to tap other assets of the family that ran the firm.

PricewaterhouseCoopers, judicial managers of Hin Leong (Pte) Ltd., has urged the family to repay creditors with 95% of their assets, estimated to be worth at least $2 billion, according to people familiar with the matter. The family could keep the remaining 5%, said the people, who asked not to be identified because the information is confidential. The Lim family hasn’t agreed to the proposal, stymying talks, the people said.

The impasse signals that the banks, which also include Singapore’s DBS Group Holdings Ltd., may face a long battle to recover any money from the insolvent firm. Executives at Hin Leong allegedly hid some US$800 million in losses for years and sold millions of barrels of oil that were collateral for bank loans, according to court documents. Lim Oon Kuin, the patriarch who founded Hin Leong, has been charged with abetment of forgery for the purpose of cheating, punishable by up to 10 years in prison.

Representatives for PwC and the Lim family didn’t immediately respond to requests for comment.

PricewaterhouseCoopers has sued Lim and his two children to recover the US$3.5 billion, including US$90 million in dividends the Lims allegedly paid themselves despite the firm’s insolvency, according to a court filing. The suit for the first time drew his children Evan Lim and Lim Huey Ching into allegations of fraud, saying that they too were “personally responsible” for the liabilities. Hin Leong has been insolvent since 2012, PwC claims in the court filing. The Straits Times reported on the lawsuit Monday.

See: Hin Leong founder OK Lim and children sued by PricewaterhouseCoopers for US$3.5 bil

The bulk of the Lims’ other business assets include Xihe Holdings Pte. and Universal Terminal Pte. Xihe owns a fleet of vessels. The family has a 41% stake in Universal Terminal, a major petroleum storage hub in Singapore, with the balance held by PetroChina Co. Ltd. and Macquarie Asia Infrastructure Fund, according to a court document dated April 17.

The Lim family also owns a few heritage properties in Singapore known locally as “Good Class Bungalows,” mansions painted in black and white that were typical during the colonial era. The creditors had suggested the family put these houses and other personal assets into the common pool to help raise money for debt repayment, one of the people said.

See also: Caveat of $27 mil lodged for Hin Leong boss' Second Avenue bungalow

HSBC, Europe’s largest bank, has the most exposure to Hin Leong at about US$600 million. DBS and ABN are on the hook for more than $250 million, based on April court filings.

Hin Leong’s judicial managers are represented by Drew & Napier LLC for the lawsuit against the Lims, according to the court filing. Davinder Singh Chambers LLC acts for the Lim family.