UBS AG, Europe's largest bank by assets, said it will write down US subprime investments by $10 billion and raise 13 billion francs ($11.5 billion) by selling stakes to investors in Singapore and the Middle East, according to a report on the website of Bloomberg. UBS expects a loss in the fourth quarter and possibly for 2007, the Zurich-based company said in an e-mailed statement today.Government of Singapore Investment Corporation Pte will invest 11 billion francs through the purchase of mandatory convertible bonds, while an unidentified Middle Eastern investor will invest 2 billion francs, UBS said in the statement. UBS follows Citigroup, the largest U.S. bank, in taking on strategic investors to bolster capital. The New York-based bank announced last month a $7.5 billion cash infusion from Abu Dhabi to replenish capital after record mortgage losses wiped out almost half its market value, the report said.