Cuban President Fidel Castro (L) with his Venezuelan counterpart Hugo Chavez, January 2007.  [AFP]

Caracas - Ailing Cuban leader Fidel Castro spoke at length by phone Tuesday with his closest ally, Hugo Chavez, on the Venezuelan president's daily radio show.

"Hello there, illustrious and dear friend, how are you?" Castro asked Chavez at the start of their conversation on the "Hello President" show.

"What joy hearing your voice, and knowing you are well, gives us," Chavez replies.

"I am listening here to 'Hello President,'" Castro said, mentioning a discussion on Venezuela's gross domestic product.

Castro, 80, has only been seen in official Cuban television and newspaper images since handing power to his brother Raul Castro, 75, in late July while recovering from gastrointestinal surgery.

The latest Cuban television footage of Castro, broadcast in late January, appeared to support official claims his recovery from surgery was going well.

The January 30 images show Castro in apparent good spirits and looking healthier than in the previous footage broadcast on October 28, though still frail.

He was shown chatting with Chavez, and saying his recovery from surgery was "far from being a lost battle."

But senior US officials have not been so optimistic about the Cuban leader's longevity.

Earlier in January, then US spy chief John Negroponte said "Castro's days or months seem to be numbered."

And Tuesday, the new director of national intelligence, Michael McConnell, said: "This year is likely to mark the end of Fidel Castro's domination of Cuba."

But McConnell added that "significant, positive change is unlikely immediately following his death."

"The period following his July operation afforded Raul Castro the opportunity to solidify his own position as successor."