British Airways is taking legal action against efforts to prevent its passengers paying for tickets with American Express credit cards.

American Express threatened the ban after BA decided to stop paying fees to the firm when customers paid for flights using corporate Amex cards.

American Express claimed the move broke an agreement with BA.

But the airline, in a statement made after a legal filing in a New York court, said it did "not believe" it had breached its contract with American Express.

"We are keen to resolve this issue."

Reduced fees

British Airways is trying to reduce booking fees it pays to third parties as it looks to turn around its worst financial performance since privatisation 15 years ago.

Almost three-quarters of top British companies use corporate Amex cards to pay for travel, so the airline is keen not to lose its relationship with American Express.

Analysts say it is likely that BA would be prepared to negotiate a reduced fee per booking to American Express.