The situation in the world’s oceans has become increasingly complicated, with the oceans once again turning into an arena of geopolitical rivalry, Russian Presidential Aide and Chairman of the Maritime Board Nikolay Patrushev said during talks in Brasilia. "The situation in the world’s oceans is currently highly challenging. The ocean is once again becoming a key arena for geopolitical rivalry," the presidential aide explained. According to Patrushev, the current situation poses serious challenges for both Russia and Brazil. It is no coincidence that a Brazilian saying goes: ‘Calm seas do not make good sailors,’" he concluded.