Patrick Frater Asia Bureau ChiefShinzo Abe is expected to resign on Friday as Prime Minister of Japan, due to health problems.The information was reported by public broadcaster NHK, citing sources close to Abe. NHK said that Abe will hold a press conference later in the afternoon to announce and explain his decision.Only days ago, Abe became Japan’s longest serving prime minister, with over seven years of tenure in his second stint.