Fidel Castro's son reportedly has said his father is in good shape despite nearly four months of public silence that in recent days set the Twitterverse aflame with speculation about the 86-year-old former president's health.

"The Comandante is well, going about his daily life, reading, doing his exercises," Alex Castro was quoted as saying by Arlin Alberty Loforte, a reporter for the Venceremos weekly newspaper in the eastern city of Guantanamo.

The exchange came at an exhibition of portraits that the younger Castro, a photographer, has taken of his father since 2010. It was reposted by a prominent pro-government blogger known as Yohandry Fontana, and state news agency AIN also reported Alex Castro's comments.