Though Japan has signed aid pacts in order to win support from ASEAN countries in its dispute with China, Japanese Prime Minister Shinzo Abe's "checkbook diplomacy" may fail because his provocative political actions put the region into a difficult situation, observers said.

On Sunday, Abe concluded a three-day Japan-ASEAN summit in Tokyo during which Japan, in what experts called "an unusual gesture", offered to provide 2 trillion yen ($19.2 billion) in aid for the 10-member bloc.

Japan also pledged fresh aid worth about $610 million in loans to Myanmar, mainly to help the Southeast Asian country's infrastructure projects.