Miguel Díaz-Canel spoke to crowds in Havana the US is trying to undermine Cuba’s political system.
He announced Washington wants total control over Cuba.
Díaz-Canel described US policies a form of political genocide during July 26 events.
He stressed this is a danger to the country's right to govern.
Raúl Castro stayed away from the largest rally.
Tensions remain high as a result of sanctions and American political pressure.