Barclays boosted its expected bill for foreign-exchange fines to more than £2 billion ($3.07 billion) on Wednesday and said it is working hard to settle investigations with global regulators.

The British bank took a new £800 million charge in the first quarter for potential fines over its foreign-exchange activities, dragging its net profit for the period down to £465 million, compared with £965 million in the same period last year.