She requested the Centre to "initiate immediate efforts to find a permanent and pragmatic solution to this livelihood issue of our fishermen."
In a letter to Modi July 6, text of which was released here Monday, Jayalalithaa referred to the arrest of 20 fishermen in four mechanised boats from Tamil Nadu by the Sri Lankan Navy July 5.
She said the fishermen were taken to Thalaimannar in Sri Lanka.
Jayalalithaa said the right of livelihood of fishermen who historically and traditionally fish in the Palk Bay is continuously infringed upon by the Sri Lankan Navy.
"The historical rights were simply signed away as part of the ill advised Indo-Sri Lankan Agreements of 1974 and 1976 which also unilaterally ceded Katchatheevu (an islet) to Sri Lanka without having any foresight or concern for the plight of our innocent fishermen," she said.
Stressing that the validity of these agreements is subject to the decision of the apex court case, Jayalalithaa said the state government "continues to reiterate that the issue of the International Maritime Boundary Line and Katchatheevu cannot be treated as a settled issue".
"Only the retrieval of Katchatheevu will ensure the restoration of safety and security of our fishermen's livelihood in the traditional waters of Palk Bay," she said.