On Sunday morning, a group of animal-lovers will march a mile down one of Havana's main thoroughfares waving placards calling for an end to animal cruelty in Cuba.

Short, seemingly simple, the march will write a small but significant line in the history of modern Cuba. The socialist government is explicitly permitting a public march unassociated with any part of the all-encompassing Communist state, a move that participants and historians call highly unusual and perhaps unprecedented since the first years of the revolution.

Still, there is no indication Cuba is moving toward unfettered freedom of assembly: The state still clamps down on unapproved political speech with swift and heavy police mobilizations, waves of arrests and temporary detentions.

In this Thursday, April. 4, 2019 photo, Grettel Montes de Oca Valdes, a professional dancer and founder of the group Cubans in Defense of Animals poses with cats that were strays in her home in Havana, Cuba. A group of animal-lovers will march a mile down one of Havana’s main thoroughfares Sunday waving placards calling for an end to animal cruelty in Cuba. Short, seemingly simple, the march will write a small but significant line in the history of modern Cuba. (AP PhotoRamon Espinosa)

In this Thursday, April. 4, 2019 photo, Grettel Montes de Oca Valdes, a professional dancer and founder of the group Cubans in Defense of Animals poses with cats that were strays in her home in Havana, Cuba. A group of animal-lovers will march a mile down one of Havana’s main thoroughfares Sunday waving placards calling for an end to animal cruelty in Cuba. Short, seemingly simple, the march will write a small but significant line in the history of modern Cuba. (AP PhotoRamon Espinosa)