Pepsi-Cola Co. has agreed to sell a stake in its Washington-area bottling operation to L.A. Lakers basketball star Earvin "Magic" Johnson and Earl Graves, a prominent black businessman and publisher of Black Enterprise magazine, creating the largest minority-operated Pepsi franchise in the country, sources said yesterday.

Pepsi officials declined to comment on the existence of such an agreement, but Pepsi has scheduled a press conference at the National Press Club on Wednesday to announce a new business partnership with Johnson and Black Enterprise.

A source who said he has known about the agreement for some time described it as a partnership between Pepsi and the two well-known investors in which Johnson and Graves will become part-owners of a franchise that currently is owned and operated by Pepsi.

Wall Street analysts said Pepsi would have good reasons to sell part of its Washington bottling operations to Johnson and Graves.

"First, all soft drink bottling companies would like to have franchise bottling operations ... in strong hands," said Roy Burry of the Kidder Peabody brokerage house.

"The second issue here is minority ownership. You are talking about an area {Washington} in which minorities are a very significant portion of the population. Companies would always want a franchisee to do business with the public. Here you have minorities to do that -- and well-known people, too. It is a very good business. It makes a lot of sense."

Johnson would not be the first high-profile basketball player to obtain an ownership stake in a lucrative bottling operation. Former Philadelphia 76ers star Julius Erving owns a stake in a Coca-Cola bottling plant in Philadelphia.

The Coke and Pepsi bottling operations are attractive businesses. The Washington-area Pepsi plant, which has its headquarters in Cheverly produces millions of cans and bottles of Pepsi annually and has the exclusive distribution rights to produce the popular Coke rival for the Washington market.

Most Pepsi franchises either are owned by independent operators or owned by Pepsi, a source said, adding that there are two independent Pepsi bottling operations in Texas and Michigan that are wholly owned by minorities.

The Pepsi agreement with Johnson and Graves, the source said, appears to represent the first time Pepsi has created a partnership by selling an ownership stake in one of its own franchises to an independent group of minority investors.

Another source familiar with the agreement said it is only the second time in 20 years that new owners have been allowed to buy a stake in a Pepsi franchise operation. But details of the agreement, including how big a stake Johnson and Graves would acquire from Pepsi, were not available.

Sources within the beverage industry said the possibility of some sort of business arrangement among Pepsi, Johnson and Graves has been rumored for the past year, and that about eight or nine months ago it was rumored that negotiations had broken down.

The source said an announcement of a partnership would not come as a surprise to those in the industry.

Johnson and Graves could not be reached for comment. Their Washington press conference scheduled for Wednesday was reported by United Press International yesterday.

Johnson is already familiar with Pepsi products. In May 1989, the company signed Johnson to a multimillion-dollar contract to promote Pepsi in radio, television and print advertisements.

In past interviews, Johnson has indicated that he is planning carefully for a career after he stops playing basketball.