British Airways has announced huge losses in its 2009-10 financial results.

British Airways (BA) has reported its biggest ever loss, with its 2009-10 financial year results showing a loss of £531 million, attributed to the volcanic ash disruption, higher costs and strike action by cabin crew, which alone cost the airline £43 million.

Willie Walsh, BA’s Chief Executive, remained positive: “Despite a £1 billion drop in revenue during the year, our determined efforts on cost control mean that costs have reduced at a comparable level and our operating loss is virtually the same as in the previous year.

“To be in the midst of the biggest economic downturn in 60 years and produce the same operating figure as last year shows the hard work that has been put into steering our business through the recession.”

The news comes as BA cabin crew plan more days of strike action, initially for five days beginning Monday 24 May, followed by further five-day periods from 30 May and 5 June.

Walsh commented: “Returning the business to profitability requires permanent change across the company and it’s disappointing that our cabin crew union fails to recognise that.”

By the end of 2010, BA plans to complete its merger with Iberia airlines, to become the International Airlines Group, which it hopes will deliver annual synergies of €400 million by its fifth year.