Steve Trow has only been leader of the council for two months following the departure of previous borough boss Steve Eling.
But he’s now told fellow Labour councillors he no longer wants the top job, citing personal reasons.
Stunned councillors were told the news just hours after Labour swept the board in local elections, winning all 24 contested seats – giving them complete control of all available 72 seats.
Now the opposition-free Labour party will begin the challenge of selecting a new leader.
'Changing personal circumstances'
In an email, the Sandwell leader cites changing personal circumstances and family obligations for his decision to step down.
He wrote: “I congratulate all of our candidates on what has been a sometimes difficult but hard fought campaign, and on another clean sweep by the Labour Party.
“The Labour Group in Sandwell now has the opportunity to continue to move forward with an undiminished commitment to improving the lives and opportunities of the many not the few.
“I am also however writing to announce that I will be stepping down as leader of the Group.
"Over recent weeks, changing personal circumstances and increasing family obligations mean that the time is right for me now to hand over to a new leadership of the council.”
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He praised the work of councillors Ann Shackleton and Kerrie Carmichael, adding: “With such dedication, Sandwell is clearly in safe hands.
"I am confident that I will now hand over to a leadership team that will take up the baton with enthusiasm and experience.”
He went on to say he would continue representing his Old Warley ward but would not be seeking any other roles or positions within the party.
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He added: “My tenure as Leader may have been shorter than I had intended, but I am sure that the people and communities of Sandwell will be able to remain confident that their future is in good hands and that on 21 May the new council leader will again have the unanimous support of all members of the Labour group.”
Over the next two weeks Labour councillors will hold internal meetings to decide who will replace Councillor Trow and appoint other party positions before the full council meets to ratify their choice of leader.
Councillor Trow has declined to comment further.