Amid the excitement over the thaw in U.S.-Cuba relations, one person has been conspicuously absent: Fidel Castro.

The former Cuban president hasn't made any public comment about the announcement that the U.S. and Cuba will restore diplomatic relations after more than 50 years of hostility.

Fidel Castro periodically has weighed in on world events in newspaper columns since he left office after falling ill in 2006.

Information about the 88-year-old Castro is scarce in Cuba and even his exact whereabouts are not officially disclosed. Some Cubans say they are sure his brother, President Raul Castro, would not have agreed to renew ties with the U.S. without the behind-the-scenes blessing of his brother.

President Raul Castro may speak Friday as the Cuban National Assembly holds one of its twice-annual sessions.