LAST SUMMER, with much fanfare, Mayor Barry appeared on television to announce a plan to get the city out of its financial crisis. It is now one quarter into the new fiscal year, and more than five months after the speech, yet not one step has been taken to put the mayor's plan into effect. In fact, the lone attempt to grab hold of the $215 million deficit in the budget was made only this week by city council finance chairman John Wilson. Mr. Wilson proposed an actual tax package -- far from ideal -- that at least would bring in the needed money over the next five years. Council chairman Arrington Dixon has made a general proposal that the city go into the private bond market to get the money, but no action has been taken on that notion. So other than Mr. Wilson's tax package, no specific remedy is in the works to deal with the city's financial ills.

By having gone this long without taking action on the problem, the city's leaders risk one of two things: either they are bringing shouts of "budget crisis" and their credibility into question, or they are displaying a total inability to deal with the crisi. In both cases, the city is doing nothing to improve its situation. This point is given added weight by the city's current inability to determine whether overspending is now taking place in city departments. That is a continuation of an old and still unresolved problem: the city does not know yet the precise amount of last year's deficit. Officials use this lack of precise information to excuse their inaction on the budget.

There is no need for the mayor and other city officials to wait to learn the exact dimensions of the deficit when its general magnitude is apparent. Time is wasting. If the mayor still wants to proceed with his plan to get some of the needed funds from the Federal Financing Bank, then he needs legislation to do that. The legislation must be approved by the council and Congress. More legislation would be needed to allow the city to borrow money for any purpose other than capital improvements. Gaining approval of that legislation will take time; the sooner it is put before the legislators, the better.

While urging the city government to get going on its financial plan, we must still note that the mayor's proposal to go to the Federal Financing Bank does not look promising at this point. David Stockman, who will be director of the federal budget under President Reagan, is not a supporter of the bank as a financing tool. A Republican-majority Senate, with new leaders in the District committees, also makes congressional approval of that strategy unlikely. So now is the time for some more realistic proposal, such as Mr. Wilson's tax package, and action on such a proposal.

Mr. Wilson's package of taxes on food, liquor, restaurants, dry cleaning, public utilities and professional licenses seems harsh and too haphazard to gain wide support. And it would probably drive some people and busineses from the city. Regretably, however, some of the steps Mr. Wilson is proposing may have to be taken. The city has little choice.As the clock continues to run and the deficit continues to mount, there will be even fewer choices. Mr. Wilson is to be applauded for having taken some immediate action; now only city officials must take action if only to propose a better remedy.