Diaz-Canel, 58, was sworn in on Thursday as president to succeed his mentor Raul Castro, 86, in a transition designed to continue rather than change the one-party socialist system, one of the last in the world.

Maduro flew to Havana the following day to congratulate him and map out further cooperation between the two countries that became strategic allies in 2000 with the rise to power in Venezuela of socialist leader Hugo Chavez.

"We come to renew hope, to renew dreams and ... above all, to visualize the 10 years ahead," Maduro told Cuban state-run media shortly before meeting with Diaz-Canel in the Palace of the Revolution.

Venezuela, which holds the world's largest oil reserves, exchanges oil for Cuban medical and other technical services, although deliveries have dropped over the past few years, hurting Cuba's already struggling economy.