The British pound has tumbled again despite intervention by the Bank of England to restore "orderly market conditions".
It announced an emergency move to buy government bonds, after the government's tax-cutting plans set the markets on a frenzy.
It calmed nerves among gilt traders but failed to stabilise the Sterling, which at one point fell against the US-dollar to around $1.50, but has since recovered slightly.
Mohamed El-Erian is president of Queens' College Cambridge University and a former deputy director of the International Monetary Fund.
He says such a move is unprecedented - and could deride confidence in the central bank.
UK correspondent Olly Barratt spoke to Guyon Espiner.
