Closely watched Citicorp, the troubled No. 1 U.S. bank, has announced it will lose more than $300 million this quarter due to mounting loan losses, while its managers are to eliminate 8,000 jobs and urge directors to cut the annual common stock dividend almost in half.

Banking industry analysts said Tuesday the slate of austerity measures fell short of what Citicorp should do to offset its heap of commercial loans gone sour. But they said the moves were constructive, and represented a tacit admission by Citicorp brass of significant balance sheet trouble."I don't think it will satisfy the bank's critics, but it's a step in the right direction," said Cheryl Swaim, a bank stock analyst with Oppenheimer & Co. in New York. "It shows that (Citicorp) management realizes the company has a problem and is doing something to address it. "

Citicorp stock rose $0.75 on the New York Stock Exchange to close at $14.125. It was off $0.125 at $13.25 when trading was halted earlier.

Once considered above criticism, Citicorp recently found itself at the center of concern about the stability of the U.S. banking industry.

Its charismatic chairman, John Reed, has maintained that "Citi" took a longer view of lending at home as well as in the Third World, so its balance sheet shouldn't be read like those of other banks. But federal regulators have been less tolerant of this as banking sector woes have deepened.

Bank stock prices have dived, too, as even Citicorp saw its formerly sterling credit rating downgraded. That drove the short-term funding costs into double digits, forcing it to seek private financing overseas.

The bank said it expected to lose between $300 million and $400 million in the fourth quarter. That was the result of adding $340 million to its reserves against loan losses, and setting aside $300 million to pay for reorganization and to meet severance obligations to dismissed employees.

The U.S. banking leader said it anticipated 1990 profits of $400 million to $500 million, against $498 million for 1989.

Citicorp said its management would urge the bank's directors to vote in January to trim the annual common stock dividend to $1 from $1.78. The move would help to shore up the bank's less-than-abundant core capital by retaining earnings rather than paying them out as dividends to stockholders.

The announcement followed a spate of reports that Citicorp, recently visited by federal examiners for an annual checkup, was increasingly pinched by rising nonperforming commercial loans. These rose $780 million in the third quarter to $4.6 billion. Citicorp offered no year-end projection.

The latest $340 million provision fell short of the billions of dollars some analysts said Citicorp must set aside. Its loan loss cushion reportedly is now at 18 percent of bad loans, vs. 57 percent at other big banks.

Citicorp, the largest U.S. bank holding company, with $227 billion in assets, said it "continues its strategic commitment to its core business activities around the globe." But it added that it is taking steps to reduce costs in the face of an ever-tougher economic and business climate.

Citicorp said it will reorganize and cut its payroll to save $500 million in annual operating costs by 1992, trimming some 8,000 staff positions, including about 3,600 jobs eliminated this year. It will take a $300 million charge to earnings this quarter to meet downscaling costs, it said.

Bank spokesman John Mahoney said all the 3,600 staff members to be let go in 1990 had either left the bank or received notice. The statement said that the 4,400 new dismissals included 1,850 "peripheral" positions in Citicorp-owned businesses which are to cease operations or be sold.