http://www.bbc.co.uk/news/world-us-canada-11226158
Fidel Castro has criticised Iranian President Mahmoud Ahmadinejad for what he called his anti-Semitic attitudes.
The former Cuban leader also warned that an escalating conflict between Iran and the West could lead to nuclear war.
Mr Castro, speaking to a US journalist, also questioned his own actions during the Cuban Missile Crisis of 1962.
Asked if he stood by his recommendation for the Soviets to bomb America, he said "it wasn't worth it at all".
Mr Castro was speaking to Jeffrey Goldberg, a journalist with The Atlantic magazine based in Washington, DC, whom he personally invited to Cuba.
Mr Castro led Cuba for almost 50 years after toppling the government in a revolution. He fell ill in 2006 and handed power to his brother Raul in 2008. Since then, his public appearances have been rare, but in recent months he has made a series of public speeches and televised appearances.
'Gradual escalation'
Mr Castro's "body may be frail, but his mind is acute, his energy level is high", wrote Goldberg on his blog on The Atlantic website.
Over the course of a five-hour discussion, Mr Castro "repeatedly returned to his excoriation of anti-Semitism", and criticised Mr Ahmadinejad for denying the Holocaust.
"The Jews have lived an existence that is much harder than ours. There is nothing that compares to the Holocaust," the former president said.
Mr Castro said that Iran could further the cause of peace by "acknowledging the 'unique' history of anti-Semitism and trying to understand why Israelis fear for their existence", Mr Goldberg wrote.
Mr Castro told Mr Goldberg that he understood Iranian fears of Israeli-American aggression and that he did not believe that sanctions and threat would dissuade Iran from pursuing nuclear weapons.
"The Iranian capacity to inflict damage is not appreciated," Mr Castro said. "Men think they can control themselves but [US President Barack] Obama could overreact and a gradual escalation could become a nuclear war."
Mr Castro has recently made a number of warnings of the danger of a nuclear war between the West and Iran.
Mr Goldberg then questioned Mr Castro about his stance during the Missile Crisis of 1962, asking if he stood by his recommendation that the Soviets bomb the US.
"After I've seen what I've seen, and knowing what I know now, it wasn't worth it all," he said.
