August 25, 1984

In one of the largest real-estate deals in New York City history, Merrill Lynch & Company signed a rental contract yesterday to move its corporate headquarters into two towers in Battery Park City. The company, the world's largest brokerage concern, will consolidate operations from 11 buildings in Manhattan into 3.9 million square feet of office space, nearly twice the space in the Empire State Building. Merrill Lynch officials declined to disclose the value of the contract, but they estimated they would save 25 percent of their occupancy costs with the consolidation. Real-estate experts estimated the total value of the rent over 25 years to be in the range of $1 billion.

Walter F. Mondale journeyed to main- street America today to denounce the Reagan Administration as ''government of the rich, by the rich and for the rich.'' ''That's what we will change in 1984,'' he buoyantly promised a sun- dappled crowd of 3,000 onlookers. ''Let the campaign begin.'' The same theme - attacking the Republicans as the party of the rich - was sounded by Geraldine A. Ferraro, Mr. Mondale's running mate, as she campaigned in Alabama. Before leaving for the South, she said she might have hesitated to accept the Vice-Presidential nomination if she had known ahead of time about the ordeal she would face over her family finances. (Page 29.)

Archbishop John J. O'Connor of New York said today that he considered it his duty to correct politicians if they offered incorrect views on Catholic teachings. ''It is my responsibility to spell out for Catholics what the church teaches,'' the Archbishop said. ''If anyone in public office wishes to differ, wishes to say that is not Catholic teaching, than that individual ought to prove it is wrong. And if an individual does attempt to articulate Catholic teaching and it is not truly Catholic teaching, it is my responsibility to say something.''

The American Telephone and Telegraph Company said yesterday that it will eliminate 11,000 management and blue-collar jobs nationwide by early next year as part of its continuing effort to cut costs. The cutbacks, which had been rumored for weeks, reflect the difficulty that A.T.& T. is having in adapting to the competitive telecommunications environment since the breakup of the Bell System on Jan. 1. In the past, A.T.& T. has routinely laid off manufacturing employees temporarily during economic downturns, but the cutbacks disclosed yesterday would be the first of their kind in modern times at the company, where lifelong employment has been commonplace. Cost-Cutting Measures A.T.& T., which has reported earnings well below its earlier projections for its first year without the local Bell operating companies, has been struggling for most of the year to bring its high costs under control. It has already frozen wages for 114,000 management- level employees, announced the closing of four plants and cut 5,000 workers from its payrolls through attrition, resignations and special early retirement programs. A.T.& T. employs 373,000 people nationwide. After a flurry of rumors throughout the day, A.T.& T. officials said late yesterday that the cutbacks would be concentrated in the 53,000-employee equipment maintenance and service operations of AT&T Technologies, the unregulated A.T.& T. subsidiary that is spearheading the parent's push into the highly competitive computer business.

In a new step toward ending decades of political violence here, the Government signed a cease-fire agreement today with one of the country's principal leftist guerrilla groups. The agreement with the guerrilla group, the April 19 Movement, also known as M-19, followed conclusion of a similar accord with two smaller rebel groups Thursday and with the powerful Colombian Revolutionary Armed Forces in March. The signing today was delayed briefly after a police ambush in which four guerrillas going to the ceremony were wounded. Colombia is the first country in Latin America's long history of leftist insurgency in which a government and a guerrilla movement have successfully negotiated an armistice.