"Azerbaijan is our principal regional partner , both in the economic and political spheres", Head of RF President's Staff Sergey Naryshkin said. "Russia- Azerbaijan relations can be characterized as strategic collaboration. Russia aims to expand its cooperation spheres with Azerbaijan. Within the recent years Russian and Azerbaijani leaders have conducted the most productive dialogues, which allow to develop our cooperation in the political, humanitarian and military spheres", 1news.az cited Naryshkin as saying.