The Watergate Hotel, office building and adjacent shopping area probably will be sold soon, it was reported in Rome and confirmed here yesterday.

The Reuter news service reported from Rome that a spokesman for the financially troubled Soceite Generale Immobilaire, which owns Watergate Improvements, Inc., and which developed the riverfront site in Foggy Bottom," is negotiating with an unnamed American group for sale of the hotel."

However, Washington sources close to the Watergate development, which also includes three co-operative apartment buildings with a total of 740 individually held units, indicated that any sale would probably include the office building and underground shopping areas. The Watergate break-in occurred in the office building on Virginia Avenue NW.

Another office building, Watergate 600 on New Hampshire Avenue, is owned by John Hancock Life Insurance Co., which owns the 110 acres of ground under the entire Watergate complex.

A Washington source said the hotel and office building probably would bring considerably more than the $45 million that Arcangelo Belli, vice chairman of Generale Immobilaire, said was being asked for the hotel.

From New York City, Watergate consultant Peter Clow commented that $45 million seemed too low for the 260-room hotel and office building and that it is unlikely the hotel would be sold separately. Conversely, the $45 million price on the hotel alone appeared to be too high.

A principal owner of Generale Imobilaire before it passed briefly into the hands of financier Michele Sindona was the Vatican. Immobilaire now is seeking funds to stave off threatened bankruptcy, Reuter reported.