The future of troubled private Indian carrier Kingfisher Airlines appears to be in further doubt as bank lenders said they could begin calling in 85 billion Rupees (£1.02 billion) of loans.

The demands from a consortium of 17 banks, led by the State Bank of India, put pressure on founder Vijay Mallya to produce any white knight investors or see the grounded airline collapse.

State Bank of India deputy managing director Shyamal Acharya was reported by the Daily Telegraph as saying: “Banks have run out of patience.

“Consortium members felt that the matter has reached a dead end. Here is a case maybe for the termination of [the] relationship. So we decided to consider recalling the loan.”

Parts of Mallaya’s brewing empire, United Breweries Group, are thought to be collateral against the Kingfisher loans, according to the newspaper.