Morton's Department Stores has closed its outlet at 7th and D Streets NW after 46 years, giving way to the continuing decline of what had been a major retail center in downtown Washington.

The store, which for years had rung up one of the strongest sales performances in local retailing, fell victim to a "diminishing market" along the 7th Street strip, said Morton's President Mortimer C. Lebowitz.

Inventory from the 22,000 square-foot store, which closed just over a week ago, has been incorporated into Morton's five remaining units, including its other downtown store at 1220 F St. NW.

Unlike the 7th Street outlet, Morton's F Street store, which opened in 1973, is "doing very well," Lebowitz said. Actually, all Morton's stores are "doing well but not as well as last year," he added, reflecting the general mood of retailers.

Morton's has no immediate plans to open another downtown store but the company is looking actively for locations in other areas of the city as well as in the suburbs.

Once the heart of a bustling commercial sector and home to four major department stores, the 7th Street corridor is "at the tail end of nowhere," said Lebowitz, who at the age of 23 opened the store with his father in 1935.

The 7th Street store had become an institution over the years, but in more recent times, Lebowitz said, "We were kind of the last gasp of the old retailing area."

He said the decision to close the store was made "fairly hurriedly" because the company had all but committed itself to "hang in" while hoping for a revival of 7th Street.

However, uncertainty about future development and a steady decline in shopper traffic along the street added to pressure to close.

Other large retailers in the area have long since departed. Both Kann's and Lansburgh department stores left within the past decade, and only Hecht's, at 7th and F streets, remains.

In addition to the shops that remain, 7th Street between G and Pennsylvania Avenue NW has become a focal point for artists.

Most merchants along 7th Street blamed the decline in business on subway construction.

"When they started to build the subway, we started desperately to look for another location," Lebowitz said. "Seventh Street was hell and just never returned."