The endorsement on Friday during a press conference at Museum London comes after the Ward 7 councillor filed candidacy papers back in May.
Morgan’s campaign announcement came two days after Holder announced he would not seek a second term as mayor, and would instead retire from political life at the end of the current council term.
During the press conference, Friday morning, Holder told reporters there was no better person for the job.
“Two years ago in October, I nominated Josh Morgan to serve as our city’s deputy mayor. Now, today, a little over two months before October’s municipal election, I am enthusiastically and wholeheartedly endorsing Josh Morgan to become London’s 65th mayor,” Holder said.