(Reuters) Unisys Corp., the giant computer maker that is trimming costs to offset an expected drop in profits, says it is offering incentives to employees who retire early or voluntarily leave the company.

Blue Bell, Pa.-based Unisys, a diversified computer and defense electronics company, did not publicly announce the work force reduction, but a spokeswoman confirmed a press report that the plan had begun.The spokeswoman would not estimate how many employees were expected to join the plan or how much it would cost. Unisys last year set aside reserves for the plan, for which about 1,000 U.S. workers are eligible, she said.

Employees who are at least 58 years old and have 15 years of service will qualify for early retirement. The workers will have two years added to their age and service record when their pensions are calculated, said the spokeswoman.

Unisys is also offering "voluntary layoff" benefits to other employees, who will receive one week's pay for each year of service, plus expanded severance pay, she said.

Unisys, the nation's third-largest computer maker, told analysts last week that its profits would suffer during the first half of 1989 as it makes a transition to its new 2200 line of powerful mainframe computers and works off about $500 million of excess inventories.

Executives said they hoped to trim Unisys' work force by about 3 percent, as they did last year. Unisys, whose earnings rose to $3.58 a share last year from $3.15 in 1987, said it expects business to pick up substantially in the second half of 1989.