The Alexandria City Council last night became the first governing body in Northern Virginia to give public employes a day off in honor of the birthday of slain civil rights leader Martin Luther King Jr. Jubilant supporters of the measure said the city was also the first locality in the entire state to make Jan. 15 a public holiday.

"Let's not waste any time reciting King's virtues," said Nelson E. Greene Sr., the council's only black member. At Greene's urging, the council decided to skip a public hearing at which more than a dozen proponents of the measure were expected to speak.

The vote was unanimous and was greeted by sustained applause and a standing ovation from more than 200 people who packed the council chamber.

City officials said the holiday, the 11th full day off with pay for the city's 1,600 employes, would cost the city about $162,000 in lost pay and overtime.

Earlier this month, the Virginia General Assembly passed a measure that would make King's birthday a state holiday. If approved by Gov. John N. Dalton, Virginia will be one of just three states along with the District of Columbia, to honor the slain civil rights leader.

The Fairfax County school system currently celebrates King's birthdate on Jan. 19 in conjunction with celebrations for confederate generals Robert E. Lee and Stonewall Jackson.

The measure in Alexandria applies only to city workers. The school system, which also employs about 1,600 people, sets its own holiday schedule, officials said.