The 1974 Agreement signed between India and Sri Lanka had determined Katchatheevu as a part of Sri Lanka, and it was ceded by the Indian Government unilaterally without obtaining the approval of both Houses of Parliament for a constitutional amendment, she said in a letter to Prime Minister Manmohan Singh.
"The stand of the Government of Tamil Nadu is that Katchatheevu has always been a part of India, geographically, culturally and historically and needs to be retrieved back, keeping in view the livelihood interests and security of thousands of Indian fishermen," she said.
The state revenue department had impleaded itself in the case in 2011 after her party came to power, Jayalalithaa said.
She also said the state assembly had unanimously passed a resolution on May 3 stating that in view of the legal invalidity of the 1974 and 1976 Agreements, the Centre should take steps to retrieve Katchatheevu and surrounding areas.
"I, therefore, request you once again to kindly take urgent measures to get back Kachatheevu and the surrounding areas from Sri Lanka. Further, the IMBL needs to be redrawn after retrieval of Katchatheevu, which will enable our fishermen to carry on fishing in their traditional fishing waters without concerns of safety and security," she said.