Global stock markets were rattled by fears that leveraged buy-out deals could dry up in the face of increasing investor aversion to risk.

Equities were unsettled after banks dealing with Kohlberg Kravis Roberts’ buy-out of Alliance Boots failed to sell £5bn of senior loans to fund the deal. Chrysler said it was suspending its $12bn auto loan deal and sweetening pricing terms on a further $6bn of loans.