An ailing Fidel Castro has said that Cuba's president was right to adopt a "dignified silence" over a Moscow newspaper report that Russia may station nuclear bombers on the island, and said Cuba doesn't owe any explanation to Washington about the story.

In a brief, cryptic essay posted on a government website on Wednesday night, the 81-year-old former president neither confirmed nor denied the Monday report in Izvestia newspaper.

Moscow is angry about US plans for missile-defence sites in Eastern Europe and Izvestia cited a "highly placed" military aviation source as saying, "While they are deploying anti-missile systems in Poland and the Czech Republic, our long-range strategic aircraft already will be landing in Cuba."

Izvestia said this apparently refers to long-range nuclear-capable bombers.

It points out that there would have to be a political decision on landing bombers in Cuba, and quoted the unnamed source as saying there have been such discussions.

A US State Department spokesman said that American officials had received no official confirmation from the Russian government about the newspaper report, and he was unaware of any US efforts to directly contact Moscow about it.

"We continue to work with the Russians on this issue," said Gonzalo R Gallegos, referring to talks aimed at explaining the US government's missile defence plan.

"We have consistently made it clear to them that our proposed deployment of a limited missile defence system in Europe poses no threat to them or to their nuclear deterrent," he added.

While Fidel Castro said the president, his brother Raul Castro, was wise not to respond to the newspaper report, he did not make clear why he was commenting.