continue building socialism,\'\' he added.
On the streets of Havana, where people often express a jaded skepticism of all things political, there was genuine excitement.
"This is the start of a new era,\'\' said Roberto Delgado, a 68-year-old retiree walking down a street in the leafy Miramar neighborhood. "It will undoubtedly be a complicated and difficult process, but something important happened today.\'\'
"I\'m mesmerized,\'\' added Regla Blanco, 48. "You thought that with all these old men, it would never end. I am very satisfied with what Raul said. He is keeping his promise.\'\'
Since taking over from Fidel in 2006, Castro has instituted a slate of important economic and social changes, expanding private enterprise, legalizing a real estate market and relaxing hated travel restrictions.
Still, the country remains ruled by the Communist Party and any opposition to it lacks legal recognition.
Castro has mentioned term limits before, but he has never said specifically when he would step down, and the concept has yet to be codified into Cuban law.
If he keeps his word, Castro will leave office no later than 2018. Cuban-American exiles in the United States have waited decades for the end of the Castro era, although they will likely be dismayed if it ends on the brothers\' terms.
Nevertheless, the promise of a change at the top could have deep significance for U.S.-Cuba ties. The wording of Washington\'s 51-year economic embargo on the island specifies that it cannot be lifted while a Castro is in charge.
When Raul Castro hinted at his retirement plans on Friday, it earned a sharp response from Rep. Ileana Ros-Lehtinen, a Cuban-American Republican from Florida, who called it a ploy.
"If dictator Raul Castro states that he will retire in five years, there will still be no real change for the Cuban people so long as the Castro brothers remain in any form of leadership position, even behind the scenes,\'\' she said. "The U.S. should not change its policy of isolation of the Cuban regime.\'\'
Fidel Castro is 86 and retired, and has appeared increasingly frail in recent months. He made a surprise appearance at Sunday\'s gathering, receiving a thunderous ovation from lawmakers.
Some analysts have speculated that the Castros would push a younger member of their family into a top job, but there was no hint of that Sunday.
While few things are ever clear in Cuba\'s hermetically sealed news environment, rumblings that Diaz-Canel, an electrical engineer by training and ex-minister of higher