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Álvaro Uribe Vélez was the strongest opponent of Juan Manuel Santos during his presidency. Uribe, a former president of Colombia himself, was a staunch conservative and opposed Santos' more liberal policies. He was particularly critical of Santos' peace deal with the FARC rebel group, which Uribe saw as a betrayal of the Colombian people. Uribe also accused Santos of corruption and mismanagement, and he frequently called for his resignation.