Britain named Canadian central bank chief Mark Carney on Monday to head the Bank of England, springing the surprise choice of a foreigner to push reform of its troubled financial system. A former Goldman Sachs investment banker who at the Bank of Canada guided the Canadian economy through the global economic crisis, Carney will succeed Mervyn King who retires in July. Carney, who already plays a leading role in setting global banking rules, defended his departure from Canada and signaled that bigger problems awaited him in London. "I'm going to where the challenges are greatest," he told an Ottawa news conference, stressing the need to "rebalance" the economy which has relied heavily on a financial services sector hit by huge losses and scandals. "It's very important for the global economy that the UK does well, that it succeeds in this rebalancing of their economy, that the reform of the British financial system is completed," he said.