Havana, May 1 (RHC-PL) -- Cuban President Raul Castro presided over the main event on International Day Workers' at Havana's Plaza de la Revolucion, where a mass parade in defense of socialism took place.

Workers, trade union leaders, government officials, intellectuals, the diplomatic corps in Cuba and leaders from a number of countries were invited to participate in the festivities.

Under the slogan 'Our Strength Is Unity' millions of Cubans gathered across the island to celebrate May 1st with the commitment to improving Cuba's revolutionary process.

The parade was also an opportunity to demand an end to the U.S. economic, financial and commercial blockade and the return of the illegally-occupied territory at the Guantanamo Naval Base.