A group of Northern Virginia developers is planning a complex of luxury houses, a health club, and a private golf course on a 2,100-acre site in Loudoun County, a partner in the group said yesterday.

The partnership, which includes former secretary of state Alexander M. Haig, is planning to build the project on Beacon Hill Farm, a vast, rolling expanse of farmland near Paeonian Springs, said James M. Wordsworth, one of seven partners.

The farm is the former residence of a Saudi Arabian prince, who bought the tract from the late entertainer Arthur Godfrey in 1979. Nearby is the home of right-wing presidential candidate Lyndon H. LaRouche Jr., a large estate guarded by armed sentries.

The partnership, Beacon Hill Farm Associates, signed a purchase contract for the property Aug. 28 for a price that Wordsworth declined to disclose. The contract has a contingency clause that would allow the group to terminate the purchase if it decides the development is not feasible, Wordsworth said.

Wordsworth said, however, he expects no snags in the plan to build between 400 and 500 luxury houses on 1,600 acres of the property. The rest of the land would be used for the club and golf course, which Wordsworth called "worldclass."

Wordsworth said the resort will seek to bring figures from around the country to Northern Virginia as both guests of the resort and as consultants designed to coordinate the resort's activities.

"If you can think of someone who's best at some activity, that person would be here," Wordsworth said, mentioning aerobics, riding and dietary assistance as among the programs the resort will feature.

"When you leave here after a week, you'll feel good. You'll be rested, six pounds lighter, and feel good about yourself," Wordsworth said.

Sources said the current owner, Prince Talal Bin Abdul Aziz, a half-brother of the king of Saudi Arabia, has not lived on the property for more than a year since he returned to his native country. Reports have said the highly secretive Talal has built a luxurious mansion on the property, which is in addition to a large manor house that has been on the farm for years.

Wordsworth said that his partnership had been negotiating the purchase for several months with the property's owner, the Vanguard Co., a Dutch Antilles corporation with which Talal is closely connected.

One of Beacon Hill's partners is Carol M. Carington, who represents the Dulles District on the Loudoun County Planning Commission. Carington said yesterday that if plans to develop the property come before the commission, she will absent herself from the meeting to avoid a conflict of interest. It is still unclear what county approval the plan would need.