This decision comes a day after Mulayam Singh Yadav snapped all ties with Kalyan Singh.
Speaking at a press conference, Kalyan said, "Mulayam had extended an olive branch to me and I accepted that. He also wanted me to join his party and when I refused he asked me to allow my son to join his party and I obliged him."
He said, "People asked me not to join hands with Mulayam as he betrays and cheats people and he (Mulayam) has proved that again today."
"The same Mulayam who is breaking ties with me now had provided me a helicopter and arranged rallies for me during the General Elections. I got them nine seats from the Chandusi region. Now that he is frustrated after the loss in recent polls he has disowned me," Kalyan added.
Kalyan Singh's son Rajbir Singh, who was also present at the press conference, announced his resignation from the post of SP general secretary and membership of the party.
"I would not like to be a part of the party where my father and our workers are not respected," Rajbir said.