There are several reasons an otherwise valid and agreed upon treaty may be rejected as a binding international agreement, most of which involve problems created at the formation of the treaty.[citation needed] For example, the serial Japan-Korea treaties of 1905, 1907 and 1910 were protested; and they were confirmed as "already null and void" in the 1965 Treaty on Basic Relations between Japan and the Republic of Korea.

When are most of the problems created that might result in an otherwise valid treaty being rejected as a binding international agreement?