Sir Peter Soulsby has reshuffled his team of assistant mayors for the second time in recent weeks.
Councillor Mohammed Dawood has stepped down and Andy Connelly has been brought in to run Leicester City Council's housing services.
Last month, Coun Dawood's role was split and responsibility for adult social care was transferred to a new assistant mayor, Rita Patel.
Sir Peter said: "We have had a change at the top. Mohammed has decided he wants to stand down for personal reasons.
"He has had a very difficult portfolio and I am very grateful for the work he has done."
Coun Dawood was unavailable for comment yesterday but a statement was issued on his behalf by the city council.
In it, he said: "Working on the executive team has been a huge challenge but also very rewarding.
"Stepping down will enable me to focus on my role as ward councillor for Spinney Hills, which I also find very rewarding.
"I would like to wish Coun Connelly good luck with the portfolio, which faces significant challenges in the times ahead."
Had Coun Dawood stayed on, he would have faced seeing through the city council's controversial homelessness strategy, which involves the closure of a large number of hostel beds, as well as a proposed 4.1 per cent rise in council tenants rents from April.
Coun Connelly will take over on a part-time basis because he wishes to keep his job as an officer of the Leicestershire branch of the Communication Workers Union.
He will be paid a special responsibility allowance of £10,964 – two thirds of that to which an assistant mayor is entitled.
Sir Peter said: "I am delighted Andy has agreed to join my team.
"He is immensely experienced and will be a very safe pair of hands with very good judgement.
"He has agreed to forgo a third of his special responsibility allowance.
"I have no doubt Andy will give 100 per cent to the role."
The change has taken place with immediate effect.
Coun Connelly said he was pleased to be asked to take on the position.
Labour sources said he has often disagreed with Sir Peter since the mayoral role was introduced.
Coun Connelly said: "It's fair to say I have been a critic. I don't have an issue with Peter personally. It is early days. I am looking forward to it."
Coun Connelly was due get his first briefing by officers on key housing issues yesterday.
Tory opposition councillor Ross Grant said: "Peter Soulsby has been saying all along that being an assistant mayor is a full-time job, but now he is allowing Andy Connelly to do it part-time.
"The other assistant mayors are full-time. Why does he think the housing portfolio is less important than any other?"
Coun Dawood is the second assistant mayor to leave the cabinet after Sir Peter took over Ted Cassidy's brief a year ago.