Image caption Billabong sponsors surfing events and competitors

The Australian surfwear brand Billabong has reported much worse than expected results as it continues to try to refinance its debt.

It reported a net loss of A$859.5m ($777.8m; £495.1m) for the year ending 30 June, compared with a loss of A$275.6m a year ago.

It has written off the value of many of its brands, including cutting the value of the Billabong brand to zero.

Its shares fell as much as 15%, having lost more than 60% in the past year.

Billabong has been struggling to maintain sales in key markets such as the US and Europe.

"They have had an absolutely ginormous writedown, and that's the only way that you can describe it," said IG Markets analyst Evan Lucas.

The firm has also been in financial trouble after an international expansion loaded the company with debt.

Billabong rejected an A$850m takeover bid from private equity firm TPG Capital Management early last year, which valued the shares at A$3.50 each. The shares ended the day at 53.5 cents.

Restructuring exercise

Chairman Ian Pollard said the year had been "the most challenging period in the company's history".

The firm, which is also facing weaker trading in its home market, Australia, has taken various steps in an attempt to revive its business.

It has closed 158 of the stores it describes as under-performing, sold the DaKine brand and all but withdrawn from its Nixon joint venture.

It is also in the process of replacing its chief executive, with an interim boss in place while it finalises the appointment of former Oakley chairman Scott Olivet.

It is also considering rival proposals to refinance its debt from two private equity firms.

"We are nearing the end of a long process that has caused distraction, impacted on staff morale and has been very costly," Mr Pollard said.

"The company looks forward to refocusing, reinvigorating its brands and rebuilding the business on a solid, long term financial footing."