Executives of large private equity firms believe they have found ways of overcoming US rules that make it difficult for their funds to buy large stakes in banks. This would position them to bolster the faltering sector without changes in regulations.

Private equity firms have trouble buying banks because federal rules bar investors holding more than 24.9 per cent of a bank from owning other kinds of companies. This was intended to prevent conglomerates taking control of banks and using them to fund themselves.