Unable to match dollar-for-dollar China's massive investment in Southeast Asia, Japan's future relevance in the region appears to hinge on it convincingly offering a "quality over quantity" approach.

Signs the government has picked up on this strategy could be seen in Prime Minister Shinzo Abe's packed diary during a series of gatherings connected to the Association of Southeast Asian Nations in the Laotian capital of Vientiane from Tuesday through Thursday.

In a summit with ASEAN leaders, Abe stressed Japan's resolve to continue to support enhanced economic integration in the 10-nation bloc with "high-quality" infrastructure investment.