Property seized by former Cuban President Fidel Castro six decades ago is at the centre of a lawsuit involving shipowner Carnival Cruise Lines.

Mickael Behn and Javier Garcia-Bengochea are suing the Miami-based cruise giant over the use of Port of Havana buildings and docks, which had been owned by their families before Castro wrested control.

Carnival has been anchoring its ships in the docks since former US President Barack Obama began efforts to improve relations with the Caribbean country, the Miami Herald reports.