Passage: Regarding the issue, Peruvian President Toledo said at the sidelines of the fourth Summit of the Americas that "the ball is in play and we're clear of our rights ... but this mustn't damage our relationship with Chile." Chile and Peru have strong business ties and many companies have cross-border investments, especially in mining, the backbone of both economies, but their relations are marred by mutual distrust that has its roots in a 19th century war in which Peru lost a swath of mineral-rich southern coast to Chile.
mustn't