Four European Union and North Atlantic Treaty Organization (NATO) members formally joined the Treaty of Amity and Cooperation in Southeast Asia (TAC) on Friday, expanding the ASEAN-led pact to 62 High Contracting Parties.
Sweden, Poland, Romania and Lithuania acceded to the 1976 treaty following the 59th ASEAN Foreign Ministers’ Meeting (AMM) in Manila.
Foreign Affairs Secretary Ma. Theresa Lazaro, who chaired the 2026 ASEAN meetings, welcomed the four countries and described their accession as proof of the treaty’s growing global relevance.
She said the move reflects ‘a shared conviction in the universality of the fundamental principles enshrined in the Treaty’ and underscores ASEAN’s role as the ‘primary driving force in shaping a rules-based regional architecture.’
Anchored on respect for sovereignty, non-interference in internal affairs, the peaceful settlement of disputes and regional cooperation, the TAC has become ASEAN’s principal instrument for promoting peace, stability and dialogue.
Lazaro also highlighted the geographic diversity of the new signatories-from the Nordic and Baltic regions to Central Europe-as evidence of the treaty’s broad international appeal.
Marking the TAC’s 50th anniversary, she likened the latest accessions to the ‘first bloom’ of the sampaguita, the Philippines’ national flower and this year’s symbol of the treaty’s golden anniversary, saying the partnership must continue to be nurtured through dialogue and mutual trust.
Representatives of the four countries reaffirmed their support for ASEAN Centrality and outlined areas for closer cooperation.
Swedish Defense Minister Pål Jonson cited opportunities in trade, security, the green and digital transitions, and science and technology.
Polish Minister Wojciech Balczun pointed to potential collaboration in defense, mining, advanced mineral processing, cybersecurity, food security, trade, investment, digitalization and the energy transition.
Romanian Education Minister Mihai Dimian emphasized academic mobility and preparing young people for an artificial intelligence-driven future, describing education as ‘one of the most powerful forms of diplomacy.’
Lithuanian Foreign Minister Kestutis Budrys said his country’s accession complements Lithuania’s Indo-Pacific Strategy. He thanked Lazaro for encouraging the move in 2024 and identified energy security, digitalization, cybersecurity, connectivity, sustainable development and people-to-people exchanges as priority areas for cooperation.
The accession ceremony capped the celebration of the TAC’s 50th anniversary. President Ferdinand Marcos Jr. was scheduled to host a gala dinner at Malacañang Palace for ASEAN foreign ministers and treaty partners later in the day.