Mike Sonko has apologised for his behaviour on national TV on Sunday, when he referred to Peter Kenneth as "an albino or whatever" and a criminal.
In an interview with Citizen TV, the Nairobi lashed out at the former Gatanga MP saying their feud was personal.
"I'm not ready for consensus with this person (Kenneth). We know what he did in 2013...he refused to step down for my boss," he said.
"Let him feel what we felt at that time...I will not accept it even if he steps down to become my running mate."
The Senator accused various people of frustrating his Nairobi governor bid and used abusive words against fellow politicians.
He barely allowed host Hussein Mohamed to ask questions as he took control of the session.
But he apologised via Twitter on Monday saying he was angry.
"Kama niliwajamisha interview ya jana poleni nilikuwa na hasira...my opponent aliniita hooligan in public...wenzake wakaniita mbwa ndani ya kanisa," he said.
This loosely translates to: "I am sorry if I angered you in yesterday's interview. I was angry. My opponent called me a hooligan in public and the others he was with called me a dog in church."
Kenyans on social media scolded Sonko for his behaviour some saying it was uncalled for.
Allan Paton said: "It is unfortunate that Mike Sonko could refer to Peter Kenneth as an albino. This shows his contempt for albinos."
Edward Meeme said the Senator made so much noise that he could hear him on TV station K24.
"Our beloved Hussein Mohamed, Sonko is disgrace to Sunday Live. Next time, spare your time by inviting Miguna Miguna, the people's choice," a user identified as Jeff Miguna Koinange said.
Miguna, who will also vie for governor, wrote: "I've just watched the most disgraceful TV interview between the primitive Mike Sonko and Mohamed. How low can the cartel media go?"
Other users jokingly told the presenter to take painkillers after the drama that unfolded during the interview.
"You'll need it more than Sonko with his [chewing] gum," Mercy Pheona said, while Monicah Wambua said the host should get an allowance for the "tough" interview.
Sonko has been opposed to Kenneth's entry to the race to take over from Governor Evans Kidero.
He said during the interview that the politician should apologise to him, Mama Ngina Kenyatta and his wife "for the tears we shed".
"I am not going to accept Kenneth as my running mate or to be his deputy. Let him feel our pain in 2013 when he did not support President Uhuru Kenyatta," he said.
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