Odisha Lok Sabha MP Baijayant Panda, who was suspended from the primary membership of the Biju Janata Dal (BJD) in January, quit the party on Monday.
In his three-page-long resignation letter to BJD president and Odisha Chief Minister Naveen Patnaik, Panda said he was "hurt and unhappy" over the fact that members of the ruling party did not attend the funeral of his industrialist father Bansidhar Panda, seven days ago.
"It has plumbed the absolute depths of inhumanity when neither you nor anyone from the BJD turned up to pay their last respects to my father Dr Bansidhar Panda, who as everyone knows was a very close friend, supporter and associate of Biju uncle (Biju Patnaik) for decades (sic)."
The MP also said that he was heartbroken to find out that several BJD leaders were "restrained" from attending the funeral service.
"It is with deep anguish, hurt and sorrow that I have decided to quit the kind of politics into which our BJD has descended," he wrote in the letter.
Panda was suspended from the BJD by Patnaik on January 24 for indulging in "anti-party activities".
The MP said that he would convey his decision to quit the membership of Lok Sabha to Speaker Sumitra Mahajan.
"With the BJD and you (Patnaik) yourself having made it abundantly clear that I am unwanted, it is only right for me to dissociate from it. Separately, I will be conveying my decision formally to the Honourable Speaker of the Lok Sabha to accept my resignation from that August institution upon completion of my religious obligations of bereavement," he wrote.
There was no immediate reaction from the BJD over Panda's resignation.