Japanese Prime Minister Shinzo Abe arrives in Manila today, starting a six-day diplomacy drive that will also take him to Australia, Indonesia and Vietnam.
Security, defence and economic issues will be at the top of the agenda, amid a growth in inward-looking policies and populism globally "as well as increasing political, security and economic uncertainty and ambiguity", a Japanese Foreign Ministry official said yesterday.
This means that Japan, as a "politically stable" nation, must "play a leading role in promoting close cooperation among major Asia-Pacific countries", the official added.
He cited events, such as the election of Mr Donald Trump as United States president, the impeachment of South Korean President Park Geun Hye and China's 19th National Congress this year, as contributing to the uncertain climate.
Mr Abe kicks off his whirlwind tour in the Philippines today, where he is the first head of government to visit the country since President Rodrigo Duterte took office last June.
The duo will meet in Manila for their third summit before travelling to Davao, where Mr Abe is scheduled to visit Mr Duterte's family home for breakfast tomorrow, said Philippine Foreign Affairs Secretary Perfecto Yasay yesterday.
"Apparently, they have struck a certain resonant chord. Apparently, Mr Abe wants to visit the President's house," said Mr Duterte's spokesman Ernesto Abella on Tuesday.
The two leaders are expected to launch a joint committee on economic cooperation and infrastructure while Mr Abe will likely pledge aid in drug rehabilitation and counter-terrorism measures.
Mr Yasay said agreements on projects in transport, agriculture and security cooperation are expected.
On Saturday, Mr Abe will meet his Australian counterpart Malcolm Turnbull in his home town of Sydney - instead of capital Canberra - a move that Tokyo hopes can "strengthen the personal relationship between the leaders".
They are expected to sign a revised Acquisition and Cross-Servicing defence pact that came into force in 2013, taking into account Japan's expanded military capability under a security policy named Proactive Contribution to Peace.
On Sunday, Mr Abe will meet Indonesian leader Joko Widodo in Jakarta, where they will talk business - including the Jakarta-Surabaya railway - and discuss steps to foster cooperation in maritime security.
The Jakarta Post reported on Tuesday that the two leaders will discuss how to jump-start trade between the two countries, with total exports and imports plunging 41 per cent between 2011 and 2015.
The Trade Ministry's director general for international trade negotiations Iman Pambagyo reportedly said Jakarta plans to ask Japan to lower tariffs for agriculture and fisheries shipments, which now stand at more than 10 per cent. The Japanese official said yesterday an agreement was unlikely on this trip.
Mr Abe will arrive on Monday in Hanoi - his final stop - where he will likely pledge six newly built patrol boats in a bid to promote security dialogue and defence cooperation, on top of another six used patrol boats that have been agreed on.
SIM University East Asia expert Lim Tai Wei noted Japan and the four countries already share good working ties with the US under Mr Barack Obama's administration.
Hosei University international relations professor Ippeita Nishida said Mr Abe can "build top-level confidence and demonstrate to Mr Trump the interests of the strategic five in Asia on continued US engagement in the region".
- Additional reporting by Raul Dancel in Manila