The Bharatiya Janata Party and the Jayalalithaa-led All India Anna Dravida Munnetra Kazhagam on Wednesday joined hands to contest the forthcoming Lok Sabha elections.
A decision to this effect was taken at a 45-minute meeting between BJP president Venkaiah Naidu and Jayalalithaa at her Poes Garden residence in Chennai.
Details of seat-sharing will be worked out later, Jayalalithaa and Naidu later told reporters.
This is the second time the BJP is entering into an alliance with the AIADMK. The first partnership ended in 1999.
When asked if the AIADMK will join the BJP-led National Democratic Alliance at the centre, Jayalalithaa said: "Whatever I had to tell you I have said."
Naidu said he had come to meet Jayalalithaa to discuss the political situation in the country.
Both leaders said the meeting was held in a 'cordial atmosphere'.
Naidu was assisted in his discussions by BJP general council member Sukumaran Nambiar.
On his arrival at the Chief Minister's residence, Naidu was received by senior AIADMK ministers C Ponniayan, O Paneer Selvam and D Jayakumar.