Venezuela’s president Maduro and Cuba’s president Raul Castro attend a May Day parade in Havana

Venezuela’s President Nicolas Maduro (L) and Cuba’s President Raul Castro attend a May Day parade in Havana May 1, 2015. International Workers’ Day, also known as Labour Day or May Day, commemorates the struggle of workers in industrialised countries in the 19th century for better working conditions. REUTERS/Enrique De La Osa