ZURICH, June 10 (Reuters) - Appropriate monetary and fiscal policies are needed in addition to solid macroprudential regulation to foster financial system stability, the head of the Bank for International Settlements said. Jaime Caruana, General Manager of the Basel-based institution, said expectations for what macroprudential rules alone could accomplish should be modest: They could make banks more resilient in the event of a crisis but they would not necessarily contain the bubble building up.