BA's pension liabilities are now accounted for on its balance sheet

Under the new rules, which came into force earlier this year, BA's pre-tax profits in 2004-5 will total �415m - 23% higher than previously reported.

But the value of BA's assets will be substantially lower because its large pension deficit has been included on its balance sheet for the first time.

BA has a total shortfall on its various pension schemes of �1.4bn.

'Significant impact'

Under new accounting rules agreed by the EU in 2002, all public companies are now required to account for non-cash items such as pension liabilities and the cost of employee share options on their balance sheets.

BA said the value of its assets would be reduced by between �1.2bn and �1.39bn after it applied the new rules - designed to provide common standards across the EU - to its 2004-5 accounts.

"The impacts of new accounting rules on our income statement are minor," said chief financial officer John Rishton.

"However, there will be a significant impact on our balance sheet."