Ravalomanana, who visited Swaziland last week after stepping down, has vowed to return.
In a short recorded message broadcast on a private television channel in Madagascar, he said: "Don't be afraid of anything. I will return soon."
He said protests needed to continue in order that the world could see that they would not accept an illegitimate government.
Political unrest in Madagascar has led to the deaths of at least 135 since the start of January.
Rajoelina led opposition to Ravalomanana whom he said was a dictator who was out of touch with the people.