With a bitter ethics battle potentially looming in the House, all but two top Republican and Democratic leaders have decided to skip what has become an biennial ritual: the bipartisan retreat.

Minority Whip Steny Hoyer (D-Md.) and GOP Policy Committee Chairman Christopher Cox (Calif.) are the only senior members of the elected leadership on either side of the aisle who plan to attend the weekend gathering, which will take place this Friday, Saturday and Sunday at the Greenbrier Resort in White Sulphur Springs, W.Va.

Rep. Charlie Stenholm (D-Texas), who is co-chairing the event with Rep. Ray LaHood (R-Ill.), said Speaker Dennis Hastert (R-Ill.) and Minority Leader Nancy Pelosi (D-Calif.) had originally planned to attend the weekend gathering but now have scheduling conflicts.

All of the leadership aides contacted for this article said the absence of their bosses was in no way motivated by the recent ethics concerns raised against Financial Services Chairman Mike Oxley (R-Ohio). Democrats are seriously considering filing a formal complaint, alleging that the Ohio Republican and his top aides improperly tried to force a mutual fund industry group to oust its top lobbyist, a Democrat, and hire a Republican instead.

Responding to the threat, Republicans lawmakers have vowed to retaliate if Democrats go through with a formal complaint against Oxley. Oxley’s office has denied any wrongdoing.

Hastert spokesman John Feehery said his boss has plans in his district this weekend but still generally supports the retreat’s goals and has encouraged GOP lawmakers to attend.

Pelosi spokesman Brendan Daly said his boss would be traveling internationally, although he declined to say exactly where because of security concerns.

Stenholm and LaHood downplayed the impact the leaders’ absence will have on the gathering, which has occurred every two years since 1997 and is designed to encourage comity and trust between the two parties.

“This is a Member-driven weekend,” LaHood said. “We made a conscious decision this year not to drive this thing from the top … if our leaders come to it, so be it. But we’re not going to wring our hands and have a lot of heartburn if the leaders don’t come.”

Stenholm echoed the sentiments, predicting that attendance would range from one-third to one-quarter of the House Members.

“Obviously, I’d like to see 435 Members there,” he said. “But that’s not practical or possible. Everybody’s got schedules to keep.”

But several senior leadership aides on both sides of the aisle claimed that the retreat’s attendance has waned in recent years as a result of a series of partisan skirmishes surrounding past gatherings. In recent years, Democrats have threatened to boycott the retreat but then consented to go.

Republican aides also complained that in 2001 then-Minority Leader Richard Gephardt (D-Mo.) used the retreat to gripe to the press about what he called “the indignities perpetrated” against the minority by the Speaker and the GOP leadership. Gephardt allegedly wrote a letter of complaint to Hastert but released it to the press first and gave it to the Speaker only an hour before the two were to appear before a national television audience on C-SPAN.

“The leadership decision not to show up is just a sign of the lack of success or progress the retreat has made in the past,” one senior staffer said.

LaHood and Stenholm, however, remain upbeat about the gathering’s success.

“Civility comes one Member at a time,” Stenholm said. “You don’t change the civility of an institution in one weekend. You change it one Member at a time, and I believe the institution has benefited by the relationships the retreat fosters.”

The organizers also explained that they have retooled the gathering’s goals for this year, focusing discussion sessions and speeches on major issues Congress must confront this cycle and brainstorming sessions about making the House a more family-friendly workplace.

The retreat’s revenue stream has also changed this year. The past three retreats were funded by the nonprofit Pew Charitable Trust, which provided $750,000 for each gathering. The Annenberg Foundation Trust at Sunnylands provided $1 million for this year’s three-day event as well as several follow-up sessions, according to LaHood.

After a five-hour train ride to the Greenbrier on Friday, lawmakers’ children can attend a special program while their parents listen to New York Times columnist Thomas Friedman deliver the keynote address. Grammy-nominated Bering Strait will provide the evening’s after-dinner entertainment. The following morning will begin with a session titled “Our Values — What We Say, What the World Hears,” led by Jessica Mathews, president of the Carnegie Endowment for International Peace, David Brooks of The Weekly Standard and columnist Georgie Anne Geyer.

Sunday will begin with an interfaith worship service and a session titled “Experiences and Perspectives on Life in the House: A Sense and Spirit of Community,” with former Reps. Bill Frenzel (R-Minn.) and Louis Stokes (D-Ohio), as well as Delores Beilenson, the wife of former Rep. Tony Beilenson (D-Calif.) and Mary Ann Fish, the wife of the late Rep. Hamilton Fish (R-N.Y.).