Former U.S. Secretary of State Cyrus R. Vance has resigned as a U.N. envoy to talks between Greece and Macedonia over the former Yugoslav republic's name, a U.N. spokesman said. Secretary-General Kofi Annan accepted the resignation and paid tribute to Vance as "a great statesman" whose untiring efforts had given invaluable service to the United Nations. Vance resigned for personal reasons. Vance's deputy, Matthew Nimetz, an American who has been involved in the talks since 1994, was appointed as the new envoy, the spokesman said. Vance had been trying to help settle a long-standing squabble over use of the name Macedonia. Athens insists that the only region entitled to use it is Greece's northern province.