Facing a critical Upper House election this summer, Prime Minister Shinzo Abe appears to be laying the groundwork for a controversy-free five-month Diet session, which starts Monday.

Abe's Cabinet now plans to submit only 58 government-sponsored bills to the session, which is reportedly the second-least number for any ordinary Diet session since 1945. The bills do not include any major controversial measures that would spark heated political battles between the ruling and opposition lawmakers.

However, the prime minister's strategy has already hit a snag as major turmoil appears to be in the pipeline.