Kerala Transport Minister A K Saseendran resigned on Sunday after an audio emerged in which he is heard having a lewd conversation with a woman on phone.
A five-time legislator from the Nationalist Congress Party, the minister announced the resignation at Kozhikode. The audio was released by Mangalam TV.
Earlier, Chief Minister Pinarayi Vijayan told the media that he had taken the report seriously and promised action.
Last year, CPI-M strongman and Industries Minister E P Jayarajan quit on charges of nepotism.