Montgomery Liquor Control Director George Griffin has resigned after more than a year of withering criticism from restaurateurs, bar owners and elected officials about his agency’s poor performance as the county’s sole wholesaler of alcohol.

In a terse letter made public late Friday, the county’s chief administrative officer, Timothy L. Fire­stine, said, “Effective today [Friday] at 5 p.m. Mr. Griffin will be moving on from his position as the Director of the Department of Liquor Control.”

Fariba Kassiri, an assistant chief administrative officer, will serve as interim director while the county searches for a successor, Firestine said.

Griffin, a 21-year county government veteran who has held the post since 2001, could not be reached for comment early Monday.

County Executive Isiah Leggett (D) said discussions with Firestine and Griffin about the director’s future and changes needed to improve the agency had been underway for the past couple of weeks.

“He offered his resignation and we accepted,” Leggett said. “I think he realized . . . that he had become more of a distraction than a solution.”

[County’s lucrative alcohol monopoly could be facing last call]

While many states, including Virginia, directly control distribution and sale of beer, wine and spirits, Montgomery County’s system is unusual and, critics contend, antiquated. Under state law the county is the exclusive wholesaler of alcoholic beverages for bars, restaurants, and private beer and wine stores. Montgomery also owns 25 retail stores that sell hard liquor.

The monopoly generates more than $30 million in revenue a year — money officials are reluctant to give up. But the agency has been the target of complaints from businesses and consumers about late deliveries and limited selection.

Griffin found himself on the hot seat last year before an ad hoc County Council committee looking into the department’s shortcomings. The Montgomery inspector general turned up numerous problems, including inventory and security issues at the agency’s warehouse. During the peak of the December holiday party season, the department missed a series of scheduled deliveries to restaurants, bars and retail wine and beer stores. In late 2014, NBC4 caught department drivers drinking on the job.

Two bills to change the county’s liquor operation are pending in the General Assembly. One would ask Montgomery voters to decide by referendum whether businesses can bypass the county and buy directly from private distributors. The other, more limited measure would allow bars and restaurants to buy “special order” products — rare wines and craft beers — from private sources.

Griffin’s resignation was first reported by Bethesda Beat.