(a) At any time within 45 days after enactment of an annexation resolution, the governing body of the county or counties in which the municipality is located, by at least a two–thirds majority vote, may petition the chief executive and administrative officer of the municipality for a referendum on the resolution. (b) After verifying compliance with the requirements of this section, the chief executive and administrative officer, by proclamation, shall suspend the effectiveness of the annexation resolution pending the results of the referendum.
Maryland Legal Code