Nairobi Governor Mike Sonko has been given a seven-day ultimatum by Nairobi MCAs.
The city MCAs drawn from the opposition have given Sonko one week to nominate a Deputy Governor.
The MCAs claimed that Nairobi County was a "mess" because the governor lacked a deputy to advise him.
Sonko in March unveiled a short list of 22 prominent personalities as possible replacements for his ex-deputy governor Polycarp Igathe.
Igathe resigned from his post in January after he claimed that he has failed to earn the trust of Governor Mike Sonko to enable him work at the county.
The embattled governor has blamed senior figures at State House and cartels for frustrating his efforts to transform Nairobi amid complaints by Nairobians that the city is being run badly.