The top U.S. health official offered Indonesia money and technical assistance Monday to fight bird flu, after warning it would be almost impossible to halt a pandemic if the virus mutates into a more dangerous form. U.S. Health and Human Services Secretary Mike Leavitt visited a U.S. Naval Medical Research Unit laboratory that is used for initial analysis of samples drawn from suspected bird flu patients. He later met with Indonesian President Susilo Bambang Yudhoyono, Health Minister Siti Fadilah Supari and Coordinating Minister for People's Welfare Alwi Shihab to discuss ways the two countries can cooperate more closely to fight the disease. Leavitt offered Indonesia US$2.5 million in assistance and promised to help maintaining relevant laboratories, Shihab said. The U.S. health secretary's two-day visit to Indonesia follows stops in Thailand, Cambodia, Laos and Vietnam, The Associated Press reported.