/ Updated  / Source: NBC News

HAVANA, CUBA -- Under rain and plenty of umbrellas, residents of Havana participated in the traditional May Day Parade with thousands of people shouting “revolutionary” slogans, showing signs supporting the Cuban revolution and its leaders, and even dancing “conga” or just walking at Plaza de la Revolucion.

The parade scenes were repeated around the country. The government said these parades would show the people’s unity in the “construction" of socialism.

Ulises Guilarte, the leader of Cuba's only trade union, said about the diplomatic process between the U.S. and Cuba that “some steps have been given” but “there is still a long and difficult way to walk.” Guilarte asked for an end to the U.S. embargo and for the return of the Guantanamo Naval Base.

Venezuelan President Nicolas Maduro joined Cuban President Raul Castro in the May Day event, although officials did not elaborate about the visit.

--Orlando Matos