Miguel Díaz-Canel spoke to crowds in Havana the US is trying to break down Cuba’s political system.
He said the US seeks total control over the island.
Díaz-Canel described US policies a form of political genocide during July 26 events.
He warned this is a danger to the country's sovereignty.
Raúl Castro was absent from the main rally.
Tensions stay high because of sanctions and American political pressure.