"I'm so embarassed I could die," Stockholm shadow deputy mayor Tomas Rudin, 48, told the Aftonbladet newspaper.
Rudin was stopped on February 1st by a female security guard outside a branch of state-run liquor retailer Systembolaget.
The guard saw Rudin put a bottle of whisky in his jacket. He then picked up two bottles of alcohol-free wine and proceeded to the check out. While he paid for the bottles of wine, the bottle of Highland Park whisky, which retails for 502 kronor ($77), remained in his coat.
Rudin was held until police arrived on the scene. During questioning, he claimed he was stressed during his Saturday shopping and simply forgot about the whisky in his jacket.
Rudin nevertheless admitted to the crime and was released after questioning, with formal criminal charges being filed on Wednesday.
Later on Wednesday, Rudin stepped down from his position, citing an alcohol problem.
After news of Rudin's shoplifting scandal emerged, Social Democrats in Stockholm convened a crisis meeting to discuss how to handle the situation, Sveriges Radio (SR) reported.