The D.C. City Council reversed itself yesterday and temporarily blocked construction of a controversial high-rise office building in the 1700 block of N Street NW, near Dupont Circle.

The unexpected decision to set the matter aside for at least one month was a victory for neighborhood residents and for council member John A. Wilson (D-Ward 2), who lobbied vigorously for a delay.

The reversal was a setback for John Antonelli, stepson of millionaire developer and parking magnate Dominic F. Antonelli. The younger Antonelli, with partners, plans to erect a 90-foot-high structure behind the facades of three 19th-century row houses at 1952-56 N St., just east of Connecticut Avenue.

To round out the site for the building, which has been under official consideration since 1977, Antonelli asked the city to close and transfer to him a 10-by-22-foot section of an alley. Two weeks ago, the council voted 7 to 3 to grant preliminary approval of that request. Yesterday it was expected to ratify that decision in a final action.

When the matter was called up for consideration, Jerry A. Moore Jr. (R-At large), chairman of the council's transportation committee, moved without explanation for a 30-day delay, which the council approved by voice vote. "Very frankly, I didn't have the votes" for approval of the bill, Moore explained later.

Wilson said he wanted to delay the alley closing so opponents of the office building would have time to be heard by the D.C. Court of Appeals in their lawsuit challenging a zoning variance that was granted for the project.

On another matter the council voted 10 to 2, after more than an hour of debate, to authorize existing trash haulers in the District to continue using open-bodied trucks while requiring all new vehicles to have closed bodies and compactors.

The measure also exempts D.C. haulers until Sept. 30 from paying a one-time excise tax of 7 percent on the value of their trucks if they have paid an excise tax in another state -- notably Maryland or Virginia.

The council unanimously confirmed Mayor Marion Barry's nominations of Norman Richardson as fire chief, Carroll B. Harvey as director of the General Services Department and economist Wesley M. Long for a seat on the three member D.C. Public Service Commission. It also approved six mayoral nominees for the Rental Accommodations Commission.

For the second meeting in a row, final action was delayed on a bill to require barrier-free access for the handicapped in new or renovated buildings in the city.