The prime minister announced an ex gratia of Rs 2 lakh for the next of kin of the deceased. The injured would be given Rs 50,000.
Eight people, including three children, died in the landslides that hit Kerala's hilly Wayanad district on Tuesday, according to officials.
In a post on X, Modi said, "Distressed by the landslides in parts of Wayanad. My thoughts are with all those who have lost their loved ones and prayers with those injured. Rescue ops are currently underway to assist all those affected."
"Spoke to Kerala CM Shri @pinarayivijayan and also assured all possible help from the Centre in the wake of the prevailing situation there," he said.
Official sources said the prime minister also spoke to the two Union ministers from the state, Suresh Gopi and George Kurien, over the prevailing situation.
Modi has asked BJP president J P Nadda to mobilise party workers in the region to assist in the ongoing relief work, they said.