Shares in Barclays fell 14 per cent after one of the bank’s largest Middle Eastern investors sold its entire shareholding in the UK bank in one of the biggest placings of stock ever carried out in the London market.

International Petroleum Investment Company, the investment vehicle of Sheikh Mansour bin Zayed al-Nahyan, a member of Abu Dhabi’s royal family, sold 1.3bn Barclays shares to 220 institutional investors at a price of 265p, a 17 per cent discount to the previous closing price. Barclays shares closed at 273.5p, down 42.75p.