TOKYO- The Japanese ruling Liberal Democratic Party's crushing defeat in the July 2 Tokyo metropolitan assembly poll and rapidly falling public support rates for Prime Minister Shinzo Abe's cabinet are starting to cast a dark shadow on his strategy for the breakup of the House of Representatives for a snap general election as well as constitutional amendments.

If Abe breaks up the all-important lower chamber of the Diet, the country's parliament, at the wrong time, the LDP-led ruling coalition could lose its two-thirds Lower House majority in the snap election or even suffer far greater political damage, analysts said.

Under a constitutional provision, support from at least two-thirds of all members of each of the two Diet chambers is required for the parliament to propose changes in the supreme law. The constitutional revisions then must be put to a national referendum, and support from a majority of all votes cast is necessary for them to be implemented.

While current Lower House members' four-year terms are set to end in December 2018, the enforcement on Sunday of the revised public offices election law, which redrew the electoral map for the Lower House to reduce vote-value disparities between constituencies, paved the way for the prime minister to make a decision on the dissolution of the chamber.

But Abe now does not appear to be as confident as he was before the Tokyo assembly election.

In May, Abe, also president of the LDP, showed his hope to see a revised constitution go into force in 2020. At the time, Abe was considering setting a national referendum for the constitutional revisions for the same date as that for a Lower House election that may be held in autumn 2018 following an assumed breakup of the chamber or simultaneously with an election slated for summer 2019 for the House of Councillors, the upper chamber, according to government sources.

Such a national referendum must be held sometime between 60 and 180 days after the Diet proposes constitutional revisions.

Aiming to hold a national referendum simultaneously with the next Lower House election, Abe was hoping to have the LDP submit its draft on constitutional revisions to an extraordinary Diet session to be convened in autumn this year and to see the parliament propose changes in the constitution during its regular session for 2018. The pro-constitutional revision camp is now believed to account for more than two thirds of all members of both chambers of the Diet.

Abe was apparently maneuvering to win his third term as LDP president in the party's leadership poll in autumn 2018, and then carry out shake-ups of his cabinet and the LDP leadership team, and dissolve the Lower House for a snap election.

However, the LDP saw its share in the Tokyo metropolitan assembly fall to a record low of 23 seats in the July 2 election and public support rates for the Abe cabinet fell sharply, in the wake of favoritism allegations involving a school operator run by a friend of the prime minister over its plan to open a university faculty of animal medicine in a national strategic special deregulation zone in western Japan.

Against this background, caution is increasing within in the LDP over Abe's plan to have the party submit its draft constitutional revision to the upcoming extraordinary Diet session.

If Abe sticks to his hope of seeing the Diet propose constitutional amendments, he would find it difficult to dissolve the Lower House before the Diet proposal for fear of the LDP and its Komeito ally reducing their seats in a subsequent general election, analysts said.

Meanwhile, Abe's leadership could weaken further if he is unable to break up the Lower House, they said.

Some in the LDP are urging Abe to put priority on efforts to stabilize his administration, rather than aiming for constitutional revisions.

Alarmed by a rise of Tomin First no Kai (Tokyoites first group), a regional party supported by popular Tokyo Governor Yuriko Koike, an LDP lawmaker said, "Abe should dissolve the Lower House before Tomin First possibly advances to national politics."

Still, pundits said that Abe needs to shore up the slumping public support for his cabinet before deciding on a Lower House dissolution. In the July 2 election, Tomin First became the biggest force in the assembly of the Japanese capital in place of the LDP. (Jiji Press)