The Treaty between Japan and Thailand Concerning the Continuance of Friendly Relations and the Mutual Respect of Each Other's Territorial Integrity was signed in Tokyo on 12 June 1940 by Arita Hachiro, foreign minister of the Empire of Japan, and Phya Sri Sena, envoy extraordinary and minister plenipotentiary of Thailand, in duplicate. It is not the Anglo-Thai non-aggression pact of the same day and not the alliance treaty of December 1941. The preamble reconfirms the traditional friendly relations and records that the peace and stability of East Asia are a common concern of both parties.

Article 1: the parties shall mutually respect each other's territorial integrity and hereby reaffirm the constant peace and perpetual friendship existing between them. Article 2: they shall maintain friendly contact in order to exchange information and consult on any question of common interest that may arise. Article 3: in the event of one suffering an attack from any third Power or Powers, the other undertakes not to give aid or assistance to the said Power or Powers against the party attacked. A military-alliance protocol or an assistance handbook is not set out here.

Article 4: ratification; the instruments shall be exchanged as soon as possible at Bangkok. Article 5: it comes into effect on the date of the exchange and remains in force for five years; if neither gives notice of intention to terminate six months before expiry, it continues until one year from the date of such notice. Ratifications were exchanged at Bangkok on 23 December 1940; it entered into force the same day. It was published in the Japanese official gazette on 28 December.

The League of Nations registered it on 26 July 1941, volume 204. The Japanese Foreign Ministry documentary compilation reprints the text from Nihon gaiko nenpyo narabi ni shuyo bunsho. It is not an offensive alliance; Article 3 is a negative obligation not to aid the attacker.

Cover: the National Diet Building in Tokyo, the period seat (completed in 1936); we do not claim the hall. Wikimedia Commons, free licence.

Sources consulted: Treaty between Thailand and Japan (1940); 友好関係の存続及相互の領土尊重に関する日本国タイ国間条約 (Japanese MFA compilation).