Toronto Mayor Rob Ford has informed city staff he is taking a leave of absence but has not said when he plans to return.
The statement comes one day after Mr Ford said he will seek professional help for a drinking problem.
Mr Ford was spotted leaving his house and getting into a car driven by another person this morning. Earlier, a large suitcase was seen being taken out of the house.
Mr Ford, 44, who is running for re-election, gained global notoriety last year when he admitted he had smoked crack cocaine, but at the time he refused to resign, or even take time off.
His change of heart yesterday about taking a leave of absence came as two Canadian newspapers published embarrassing reports.
The Globe and Mail reported it had seen a video that was shot last week and showed Mr Ford using what appeared to be drugs. Also, the Toronto Sun reported on a recording it had obtained of Mr Ford ranting and swearing at a suburban Toronto bar on Monday.
"I have a problem with alcohol, and the choices I have made while under the influence. I have struggled with this for some time," Mr Ford said in his statement.
"I have tried to deal with these issues by myself over the past year. I know that I need professional help and I am now 100% committed to getting myself right."
Allegations about Mr Ford's drug use began in May of last year, when two media outlets said they had seen video of him smoking from what appeared to be a crack pipe.
He initially said he did not smoke crack cocaine, before admitting in November that he had indeed done so. He said at the time that the incident had probably happened "in one of my drunken stupors," but he insisted he was not an addict.
The Globe and Mail said on Wednesday that two of its reporters had seen a video of Mr Ford taking a drag from a long copper-coloured pipe. The Globe said the video was secretly filmed early Saturday morning by a self-professed drug dealer.
Mr Ford's office and campaign did not respond to requests for comment. The authenticity of the video has not yet been confirmed.
The Toronto Sun reported on Wednesday that in the new audio recording it had obtained, Mr Ford used offensive language in a bar and made lewd remarks about a female candidate who is running against him in October's mayoral election.
Mr Ford, who came to power in 2010 on a platform of cost-cutting and low taxes, has billed himself as a champion of taxpayers and ordinary people.
Last year's revelation about crack use and Mr Ford's decision to remain in office made headlines globally and drew ridicule from late-night talk show hosts.
Mr Ford pledged at the time that he would stay away from drugs and alcohol.
In January, a video was posted online showing Mr Ford ranting and slurring his words at a suburban eatery. He conceded he had been drinking the night the video was shot, but described it as a "minor setback" and said his personal life did not interfere with his job.
Mr Ford, who has been stripped of many of his powers by Toronto's city council, has said he expects to be returned to office in the October election.