SHARM EL-SHEIKH (Reuters) - U.S. President George W. Bush said on Saturday Lebanon was facing a "defining moment" and pledged that the United States would stand by the pro-Western government of Prime Minister Fouad Siniora against Hezbollah.

Speaking to reporters on a visit to Sharm el-Sheikh, Bush accused "radical elements" of trying to undermine the Lebanese government. "It's a defining moment," he said.

(Reporting by Matt Spetalnick; editing by Keith Weir)