Japanese Prime Minister Shinzo Abe's expressed intention to build closer security ties with Asean may displease China, but Beijing will not overly worry given its strong ties with the South-east Asian grouping.
As for Asean, at least one member has openly welcomed Japan's move. Most, however, have kept silent - indicating that states without any territorial dispute with China are treating it with caution.
Mr Abe, in his keynote speech on Friday at the Shangri-La Dialogue organised by the International Institute for Strategic Studies, said Japan "will offer its utmost support for the efforts of the countries of Asean as they work to ensure the security of the seas and the skies, and thoroughly maintain freedom of navigation and freedom of overflight".
While he did not elaborate on what the support might be, he pointed out that Japan has provided three new patrol vessels to Indonesia through grant aid, and that it will provide 10 such vessels to the Philippines. It is also looking at the possibility of providing such vessels to Vietnam.
Analysts said Mr Abe could have several motivations for such a move. For one thing, it could divert China's attention and resources from the East China Sea, where the two neighbours have rival claims over the islands known to the Chinese as Diaoyu and to the Japanese as Senkaku.
Beijing has been challenging Tokyo's control of the islands by sending ships to the area periodically.
More broadly, said Associate Professor Li Mingjiang of the S. Rajaratnam School of International Studies, Mr Abe is hoping to build a "loose regional coalition against China so as to put pressure on China and try to make China less assertive" in its maritime and territorial disputes with states in the region.
Indonesia has openly welcomed Mr Abe's move, and other states with overlapping claims with China are likely to support it too, as it will likely bolster their confidence.
Asked by The Sunday Times whether Indonesia and Asean should welcome Japan's move, Indonesian Defence Minister Purnomo Yusgiantoro said "yes", explaining, "we want to see the region in peace and secure".
While Indonesia has no overlapping territorial claims in the South China Sea with China, four other Asean states do - Brunei, Malaysia, the Philippines and Vietnam. Manila and Hanoi have had recent skirmishes with Beijing over their rival claims.
Although Asean may not have a united position on Japan's closer security links with the region, this is unlikely to divide the grouping, said Prof Li.
But China will be closely watching what Japan does next. A key question would be whether Tokyo succeeds in undermining China's security and influence in the region.
Chinese international relations expert Jin Canrong of Renmin University argued that China should not be overly worried because its overall relationship with Asean "is very good", and that the grouping can only move closer economically to Beijing given Japan's declining economy.
Still, Tokyo's move and the United States' pivot to Asia might prompt Beijing to calibrate its security policy towards the grouping, such as by taking steps to shore up ties with those closer to China, and isolating others that ally themselves more closely with Japan and the US.
At the same time, as an unpeaceful region would be detrimental to China, it could be more willing to hold negotiations on the Code of Conduct to manage disputes in the South China Sea, which would act as a restraint on the behaviour of all claimant states, including China.
If, indeed, Mr Abe's move would hasten the completion of the code, it would be a gain for Asean. But for Japan, it may not have all the effects it desires.