HAVANA (Reuters) - Cuba's communist-run government on Monday slashed by a quarter the weight of its subsidized ration of daily bread, the latest shortage to strain a decades-old subsidies scheme created by the late Fidel Castro.

The bread, one of a handful of still subsidized basic food products in Cuba, will be reduced from 80 grams to 60 grams (2.1 oz), or approximately the weight of an average cookie or a small bar of soap. Its price, too, was slightly reduced, to just under 1 peso, or 1/3 of a cent.

Still, many Cubans, who earn around 4648 pesos a month, or around $15, can scarcely afford to shop for more expensive bread on the private market, leaving them with few alternatives.

"We have to accept it, what else can we do?" Havana-resident Dolores Fernandez told Reuters while she stood outside a bakery on Monday. "There's no choice."

Cuba last week said it had run short of the wheat flour it needs to produce the bread, a predicament the government blames on the U.S. trade embargo, a complex web of restrictions that complicates Cuba's global financial transactions.

The Caribbean island nation is suffering from extreme shortages of food, fuel and medicine, shortfalls that have primed a record-breaking exodus of its citizens to the nearby United States.

Cuba's ration book, or "libreta," as it is known among island residents, was once considered a hallmark of Fidel Castro's 1959 revolution, providing a range of deeply-discounted products to all Cubans, including bread, fish, meat, milk, and cleaning and toiletry supplies.

Today, the crisis-racked government offers just a fraction of those products, and often, they arrive late, in poor quality or not at all.

Bernardo Matos, of Havana, said he had not detected a change in bread size on Monday, but said he was unhappy with the quality.

"The quality is terrible," he said shortly after purchasing his ration. "The flour tastes like acid."

Cuba's government has said it planned to reinforce inspections at state bakeries to assure quality does not suffer.

Cuba earlier this year sought help from the World Food Programme to guarantee the supply of subsidized powdered milk for children, another key staple of the Cuban ration book that has recently grown scarce.

Beyond the few remaining centrally planned economies like Cuba's and North Korea's, rationing is typically only used during war-time, natural disasters or specific contingencies.

(Reporting by Mario Fuentes and Alien Fernandez, writing by Dave Sherwood; Editing by Marguerita Choy)