leaking of confidential documents to WikiLeaks is unfortunate and will complicate international diplomacy, the U.N. chief said on Friday. "It's unfortunate that these confidential documents have been leaked," Reuters quoted U.N. Secretary-General Ban Ki-moon as telling reporters in New York. "But whatever the motivations of this leakage might be on the part of leakers, this will make it very difficult for the normal and reasonable conduct of business, particularly in the diplomatic world," he said. For weeks WikiLeaks' founder, Australian computer hacker Julian Assange, and his colleagues have been releasing secret U.S. diplomatic cables on their website and teaming up with newspapers around the globe to amplify the impact of the disclosures, some of which have been highly embarrassing to the United States and other countries.