MOSCOW—With severe political instability, economic woes and a war in Chechnya threatening to tear Russia apart, Kremlin officials announced today that a man with a big stick will step forward to lead the troubled nation. Ailing prime minister Boris Yeltsin declared that he will step aside willingly, provided the unnamed stick-wielder was an imposing, burly man equipped with a stick of sufficient size to command total obedience and control. Russian officials have not ruled out the possibility of also equipping the man with large, hob-nailed boots.