Nairobi Governor Evans Kidero says former presidential aspirant Peter Kenneth can only win an MCA seat due to his political 'inconsistency'.
The two leaders shared a podium for the first time in a local church on Sunday ever since Kenneth declared his intention to challenge Kidero.
Kenneth, who emerged fourth in 2013 presidential elections, has since resigned from Kenya National Congress and subsequently joined the ruling Jubilee Party.
"My brother (Kenneth) is not sure what he is looking for. He is unfit for this job because he doesn't understand what it entails," he said.
Kidero added amid laughter: "I think he can do well as an MCA so that he helps me change Nairobi through legislation. It is a shame that you get out of a presidential ballot box to Governor."
Earlier, Kenneth had poked holes into Kidero's leadership arguing that he lacked a plan to de-congest and clean Nairobi County.
Kenneth will however, face flamboyant Nairobi senator Mike Sonko who is keen to win Jubilee ticket for gubernatorial seat.