Acting president Raul Castro complained to lawmakers about inefficiencies in the island's economy, telling them in comments made public Saturday that there is no excuse for the transportation and food production problems that anger many Cubans.

"In this Revolution we are tired of excuses," he said, giving the strongest sense yet of the frank and demanding leadership style he will likely adopt if his ailing older brother Fidel Castro does not return as president.

After almost five months in power, it has become clear that the 75-year-old Raul Castro will call officials to account for their actions and demand they produce real results, rather than offer mere political platitudes.

He also has shown a willingness to criticize aspects of the communist system that are not working.

"The Revolution cannot lie," he said in comments published by the Communist Party newspaper Granma. "This isn't saying that there have been comrades who have lied, but the imprecision, inexact data, consciously or unconsciously masked, can no longer continue."

Castro spoke Friday afternoon during a year-end meeting of the National Assembly. He did not address the two-hour session that international journalists were allowed to attend in the morning.

Excerpts of his comments aired later on state television showed him looking gruff and almost angry as spoke in a strong, controlled tone about problems affecting average Cubans.

It was unknown how long he spoke, but Castro tends toward short speeches with concrete messages on local matters — a sharp contrast to his older brother's extemporaneous discourses that often ran many hours while ranging over philosophical thoughts on world and Cuban affairs.

Lacking the charisma of his more famous brother, Castro will need to make changes that improve the lives of Cubans to gain the popular support necessary to govern over the long run.

Public transportation problems top the list of Cubans' many complaints about the system, a litany that includes crumbling housing, insufficient food for their families and government paychecks that don't cover basic expenses.

Castro's willingness to publicly criticize the system's failings is a switch from the past policy under his brother of extolling the virtues of the revolution while blaming a handful of corrupt individuals for problems.

But it is too early to know whether his frankness could evolve into a more generalized kind of Cuban glasnost, the policy of openness in public discussions that was promoted by Soviet leader Mikhail Gorbachev in the late 1980s.

Fidel Castro, 80, temporarily ceded his powers to his brother July 31 when it was announced he had undergone emergency surgery for intestinal bleeding. He has not appeared in public since, and looked thin and frail in a government video released in late October.

Fidel's medical condition is a state secret, but Cuban authorities deny he suffers from terminal cancer as U.S. intelligence officials say. Yet officials also have stopped insisting he will return to power, making it more probable that Raul, his constitutionally designated successor, will eventually assume a permanent role.

Unlike Fidel, who in recent year rolled back modest economic reforms adopted in the 1990s, Raul is believed to favor a limited opening up of the economy.

Raul, who also is defense minister, has long railed against government inefficiency.

During Friday's parliamentary session, he criticized the "bureaucratic red tape" preventing the government from completing payments to the individual farmers and cooperatives producing 65 percent of the island's vegetables.

In excerpts of his comments aired Friday night on state television, Castro also criticized efforts to improve Cuba's dilapidated public transportation, saying it is "practically on the point of collapse."

Phil Peters, an analyst at the Lexington Institute, a think tank in suburban Washington, said the willingness to blame systemic problems rather than the moral failings of individuals was underscored in October in a newspaper series on petty corruption.

The Communist youth newspaper Juventud Rebelde told of a state cafeteria where patrons who paid for one-third of a liter of beer got one-fourth instead, letting employees skim the difference from the cash register. A government-employed cobbler charged three times the official rate because he had to buy his own supplies.

The articles told Cubans the government recognizes "that law enforcement alone is not the solution to the problem," Peters wrote in a recent institute newsletter.

"The article did not say what Cuba's interim president believes would inspire allegiance to the revolutionary project if old war stories do not suffice; that question was left hanging," Peters concluded. "The coming year will tell us if economic policy change is his answer."