District of Columbia Mayor Marion Barry plans to ask Congress for about $12 million to provide 14,000 additional summer jobs for city youths and he plans to set aside 10 percent of all new jobs in the District government for persons now on welfare.

Barry disclosed these proposals yesterday during an early-morning, twohour meeting of his cabinet at which the emphasis in discussions was on ways to cut city expenses, improve management of the city bureaucracy and deal with unemployment problems in Washington.

The cabinet meeting, attended by more than 50 city department, office and agency heads, was both in its style and substance a further indication of the direction in which Barry's one-month-old administration hopes to take the city's 45,000-worker, $2 billion-a-year bureaucracy.

The long, closed-door meeting -- with its planned agenda, 8:30 a.m. start, free exchange of information and city bureaucrats scribbling notes -- was in sharp contrast to the governmental style of Barry's predecessor, Walter E. Washington.

Washington held less than half a dozen cabinet meetings a year, rarely come to work himself before 10 a.m., seldom had prepared agendas for the meetings and often rembled on while reporters scribbled notes but city department heads listened and wrote down virtually nothing.

Yesterday's was the second meeting of the Barry cabinet.The first was held Jan. 12. Unlike Washington's sessions, reporters were barred from the Barry meeting, but afterward press secretary Florence Tate gave a briefing on the meeting.

Asssistant City Administrator Gladys W. Mack, who directs the District's budget operations, said there were two overriding themes at yesterday's meeting.

"In the budget area, he wanted to make sure that budgets were adequately prepared and he wanted to stress efficiency. The budget is tight and we've just got to be aware and sensitive to costs," Mack said.

"He also wanted people to lay out on the table the problem they were working on," she said.

It was in the area of budget discusssions that Barry disclosed plans to ask congress within the next two weeks for more youth jobs funds. The money would come as part of a request for the remaining $65 million in federal payment funds authorized for city use in the fiscal year ending next Sept. 30.

If granted, the money would double the number of summer jobs for youths offered by the city. Tate said the jobs would be in addition to 4,000 youth jobs expected to be available in private businesses.

Barry talked about the need to employ more persons on welfare toward the end of the meeting, during which time he also stressed the need for more jobs in city government for two interest groups that strongly supported his campaign -- women and Lations, Tate said.

Barry also told the cabinet he intends to place much more emphasis on the city's long troubled effort to increase the amount of city funds given to minority contractors.

In 1976, the City Council passed a law providing that 25 percent of all city contracts be given to minorityowned firms. Lack of funds and political and internal problems on the seven-member Minority Business Opportunity Commission, which oversees the program, have prevented full implementation.

Barry has assigned a fellow, onetime black power activist an old friend, Courtland Cox, to be executive director of the commission and plans soon to fill the two vacancies on the commission.

Cox said yesterday that the agency would probably launch an effort to in vestigate possible fraud in the program by white firms with minority fronts, and would also push the portion of contracts given minorities well beyond the current legal level.

"Our view is that we're talking about a floor, not a ceiling," Cox said. "We're talking about not less than 25 percent as opposed to a goal of 25 percent."

The conversation around the huge, oblong table in the blue-curtained mayor's conference room was not all optimistic, however.

James R. Montgomery, acting superintendent of insurance, warned Barry that the city was facing a "touchy political" issue in trying to resolve problems with workers compensation insurance rates, which have risen by 550 percent in the city since 1972.

Montgomery said many businesses are threatening to leave the city because the rates here, which are based on a longstanding federal law, are higher than in the suburbs.

"The business people are concerned because the rates are spiraling and will more than likley continue to spiral," Montgomery said. "Other people who represent labor may think that tightening the laws should not be brought about."

Barry also asked city department heads to look for ways to cut utility costs and he directed them to avoid overspending their budgets. He reported that the executive secretary's office had overspent its budget last year by $300,000 to $400,000 -- to cover unexpected costs of printing the weekly D.C. Register.

Press secretary Tate said the cabinet meeting was told that the city's housing department had on record at times more than $1 million in uncollected rents and a $2.5 million deficit in its public housing program.

(Last May, a General Accounting Office audit had found that the District lost more than $900,000 in revenue during the first six months of 1976 because of incorrect rent charges to public housing tenants).

Barry informed his cabinet that the socially coveted low-numbered auto tags would be more broadly distributed in his administration. Those with three or four tags in their families would have to settle for one, Tate quoted the mayor as saying.

The mayor also received a report from personnel director George R. Harrod, chairman of a "Lunch Period Committee," set up to determine if city employes have been taking too much time for lunch.

Harrod recommended that the city continue to allow employes 30 minutes for lunch, except in those instances where regulations are in effect. At the mayor's request, however, a survey of 10 percent of the city's work force will be taken to determine if it might be better to allow a longer lunch hour compensated for by a corresponding lengthening of the official work day.

After the cabinet meeting, with transportation director Douglas N. Schneider Jr., said, "These things are are great. In the first place, there's an agenda. It's formal but it's very crisp."

"Its obvious that the mayor is in charge and he knows what he's talking about" said Schneider, who had previously served in the same position in the Walter Washington administration. "The other thing is that it's all substance. You come out thinking you've done some work. Afterwards, I feel inspired."

Environmental services director Herbert L. Tucker, who also served in the Washington administration, said the new administration's style has changed his work day.

"I told my people," Tucker said afterwards, "I don't know about you, but I don't see how you can expect someone to continue to come in at 8:30 and leave at 4:45 (the official city work day) every day at this pace."