By Jonathan Browning

Anil Ambani is running out of time.

The brother of one of Asia’s most wealthy men and a one-time billionaire himself lost an attempt to appeal a UK court order that he set aside $100 million in his dispute with three Chinese banks.

Anil Ambani has until 4:00 p.m. Friday in London to make the payment into court or run the risk of automatically losing the lawsuit over $700 million in defaulted loans. Failing to make the payment would mean the banks could seek a summary judgment, and allow them to move forward with attempts to seize Ambani’s assets in India or elsewhere.

His last-minute effort to postpone the deadline failed after an appeal court judge ruled Thursday that his application “had no real prospect of success and is totally without merit.”

The claim was filed by three state-controlled Chinese banks including Industrial & Commercial Bank of China Ltd., which argue that they provided a loan of $925 million to Ambani’s Reliance Communications Ltd. in 2012 with the condition that he personally guarantee the debt. The firm filed for bankruptcy last year.

Ambani has contested the personal guarantee ahead of a full trial. A representative declined to immediately comment. His U.K. attorneys didn’t immediately respond to calls and emails seeking comment.

The 60-year-old is the younger brother of Mukesh Ambani, who was until earlier this year the wealthiest man in Asia. Mukesh has bailed his brother out in the past, making a last-minute payment in an Indian case that would have seen Anil imprisoned. But Mukesh has himself seen his fortune nearly halve in the last few weeks after oil prices collapsed. He is still worth $34 billion.

Meanwhile, Anil Ambani has pleaded poverty, saying that his net worth was zero.

“The value of my investments has collapsed,” he told Judge David Waksman in February.

But at that hearing, the judge ruled that Anil Ambani or a member of his family must still put up the cash. He said he didn’t believe that his family wouldn’t help.

“What I’m dealing with is an extraordinarily wealthy family who have helped each other in the past,” he said. Waksman said he didn’t accept that Ambani’s family “have firmly and irrevocably brought the shutters down.”