Struggling Kingfisher Airlines today said its net loss widened by a whopping 147 per cent to Rs 650.8 crore in the quarter ended June, from Rs 263.5 crore in the year-ago period.

This was due to higher interest costs and cost on grounded planes even as curtailed operations helped the airlines trim operational expenses significantly.

Among the three listed airlines, liquor baron Vijay Mallya's carrier is the only one to have reported losses in the first quarter.

The other two--Jet Airways and Spicejet-- registered surprise profits after being in the red for five consecutive quarters, driven by better operating margins on the back of lower oil prices and higher seat factor.

"Though there have been reduction in operating expenses, the impact of high fuel cost, high interest rate, rupee fall and extra-ordinary expenses on account of return of aircraft to the lessors and the cost associated with grounded planes have resulted in a net loss of Rs 651 crore during the reporting quarter," the airline said in an exchange filing.

In the last fortnight, Spicejet reported a Rs 56 crore surprise profit in the June quarter on the back of improved capacity, cost-cutting and better realisation, while the largest carrier Jet Group reported a Rs 35.4 crore profit in the same period.

Total income of Kingfisher during the reporting period fell nearly five-fold to Rs 301.38 crore from Rs 1,907 crore during the year-ago period.

The carrier, launched in 2005, has substantially reduced its operations as part of a revival strategy and also returned some of its leased aircraft during the period.