Debt-ridden and with no customers, Kingfisher Airlines Ltd (KING.NS) posted a 7.55 billion rupees loss in the three months to December 31 as its planes sat idle, creditors circled and regulators rebuffed the Indian airline's revival plans.

Kingfisher, which has been stripped of its flying licence, owes an estimated $2.5 billion to banks, staff, airports and oil companies, but maintained it was "a going concern" in its results statement.

The airline, once India's second-biggest, has spent the past few months negotiating with its creditors and India's aviation authorities. The country's civil aviation minister has said Kingfisher needs at least $186 million to fly again.

Kingfisher's auditors, B.K. Ramadhyani & Co, said in its quarterly review report that an accounting method used by the airline to calculate costs incurred for aircraft maintenance and repairs was "not in accordance with generally accepted accounting standards prevalent in India."

Had it used generally accepted accounting standards, the loss for the quarter would have been 10.90 billion rupees, the auditor said in the report that was issued by the stock exchange.

Kingfisher spent 4.01 billion rupees on finance costs during the quarter and 1.82 billion rupees on aircraft leasing charges, although none of the planes was used during the period.

Shares in Kingfisher fell 2 percent on Monday ahead of the results release. Its shares have fallen 56 percent over the past year, making it the third worst-performing global airline in terms of stock price, according to Thomson Reuters Starmine.

Kingfisher, controlled by liquor baron Vijay Mallya, has never posted a profit in its eight years of operations, and lost a combined 33.1 billion rupees in 2012.