Pressure mounted on Gov. Narain Dutt Tiwari to quit after the tape allegedly showing him in bed with three women was broadcast Friday, prompting the opposition and women's right groups to hold street protests in Hyderabad, Andhra Pradesh's state capital, demanding his resignation.
Tiwari's office denied the allegation, denouncing the tape as fabricated.
Tiwari, a veteran governing Congress party leader at the national level, sent his resignation letter to the Indian president on Saturday, citing health reasons, a state official said on condition of anonymity as he was not authorized to talk to reporters.
"The news channel report is fabricated, false and malicious to tarnish the image of the governor," said a statement issued by Aryendra Sharma, an aide to the governor.
The three women were brought to Hyderabad by another woman who was allegedly promised a mining lease by the governor in return for sexual favors, ABN Andhra Jyoti News reported.
The woman said she decided to expose Tiwari through a sting operation after he did not keep his promise, the channel said.
A court stopped the channel from broadcasting the tape again later Friday after a petition filed by Sharma, who argued the video was "likely to demean and denigrate his office."
Tiwari earlier served as the top elected official of northern Uttar Pradesh and Uttrakhand states and as a federal minister.