Pope John XXIII
Mater et Magistra §172
Mater et Magistra: On Christianity and Social Progress
172 Let us be quite clear on this point. A nation that acted from these motives would in fact be introducing a new form of colonialism—cleverly disguised, no doubt, but actually reflecting that older, outdated type from which many nations have recently emerged. Such action would, moreover, have harmful impact on international relations, and constitute a menace to world peace.
Source: Mater et Magistra (Vatican.va)