Abu Dhabi investor Aabar Investments is set to buy more shares in UniCredit in the Italian bank's upcoming EUR13bn (USD14bn) share offer, Italy's biggest ever cash call, three sources said on Wednesday. UniCredit will launch the share offer next month to boost its capital base as it embarks on a restructuring plan under new CEO Jean Pierre Mustier. UniCredit has already found a group of banks ready to mop up any unsold shares.  Mustier last month unveiled a plan to shift EUR17.7bn in bad debts off UniCredit's balance sheet, cut 14,000 jobs and close 944 branches by the end of 2019. One of the three sources familiar with the matter said Aabar had confidence in UniCredit's strategy and would buy new shares to keep its stake unchanged. Given the cash call's size, Aabar would need to invest around EUR650mn to maintain its 5% stake that makes it UniCredit's second-biggest shareholder behind U.S. investor Capital Research and Management Company. (Reuters)