Major League Baseball and Baltimore Orioles owner Peter G. Angelos moved closer to agreement on a compensation package yesterday as District officials prepared for what they hoped would be a formal announcement today that baseball would return to the nation's capital after a 33-year absence.

The broad outlines of an agreement were in place last night that would give Angelos certain financial guarantees to offset the impact of a team in Washington. Although the Orioles owner said more discussions were needed before a deal is finalized, District officials said they believed Angelos was no longer an obstacle to the Montreal Expos' arrival in the city in time for Opening Day 2005.

Mayor Anthony A. Williams said he expected to hear from baseball "in the next 48 hours."

By late afternoon, Williams had summoned key D.C. Council members to a meeting in his conference room to lay out a detailed itinerary for today's events.

According to two people who attended the meeting, Williams said he expects to receive a call from Commissioner Bud Selig sometime this morning and to make a formal announcement shortly after noon on the steps of City Hall.

Within hours, however, plans had changed again, sources said. The call from Selig would come in the afternoon. The announcement would take place at the City Museum, to be followed by a big celebration featuring a few members of the old Washington Senators ballclub. Afterward, festivities are scheduled to move to the downtown restaurant Georgia Brown's.

As they left the mayor's office around 5:30 p.m., council members declined to comment, saying only that they expect a "major announcement." Selig could not be reached to comment.

Council chairman Linda W. Cropp (D-At Large) said through a spokesman that the city has scheduled a news conference for 5 p.m. today and that she is "very hopeful."

An announcement on the Expos' fate was needed by the end of the week in order to give the D.C. Council enough time to approve the legislation for the stadium and the $13 million it will cost to renovate Robert F. Kennedy Memorial Stadium, where the team would play for three seasons. With that deadline looming, Major League Baseball President Robert A. DuPuy and Angelos met yesterday for six hours of negotiations in Angelos's Baltimore law offices. Angelos has indicated he would take legal action if the Expos moved without his agreement.

Angelos called the negotiations "a work in progress. We are trying to make a deal, but we have not reached a point of agreement."

Said DuPuy: "We had a very constructive dialogue and explored a number of areas of concern on his part, consistent with his desire to protect the franchise and protect the Baltimore community. No agreement was reached, but a number of ideas were offered for consideration. I'm going back to review those with the commissioner and members of our staff."

District officials were confident that an announcement was imminent.

Mark H. Tuohey, chairman of the D.C. Sports and Entertainment Commission and the city's point man on the Expos deal, said he did not believe the lack of an agreement with Angelos "has any impact on the decision [Major League Baseball] is expected to make. That is my sense from the various discussions I have had with Major League Baseball. It is a negotiation between baseball and Mr. Angelos. It is on its own track."

The city has promised to build a $400 million stadium on the Anacostia waterfront, where the Expos, who will likely be renamed by their new owner, will play starting in the 2008 season. Renovations to RFK, where the team will play until its new home is completed, will take at least three months, according to Tuohey.

Before going into yesterday's meeting, Angelos said he would agree to a team in Washington if baseball met certain conditions. "Those conditions are the preservation of the franchise, the protection of the asset and the safety of the revenue stream," Angelos said yesterday morning. "If those ingredients are present, an agreement can be struck."

The three-pronged proposal calls for the Orioles' participation in a regional sports network together with the Washington team; for baseball to make up for any revenue shortfall the Orioles might suffer because of the new team; and for baseball to also guarantee the Orioles' value will not decline below a certain level in the event of a sale. Baseball would make up the difference, according to people familiar with the negotiations.

Angelos reportedly wants the financial guarantees to be effective indefinitely, while baseball wants the guarantees to last only as long as Angelos owns the team.

In addition to Angelos and DuPuy, others attending yesterday's meeting in Baltimore were H. Russell Smouse, the Orioles' general legal counsel; Orioles chief operating officer Joe Foss; and attorney William H. Schweitzer, managing partner at the Washington office of Baker & Hostetler, who serves as an advisor to baseball.

Baseball's 29 owners purchased the Expos for $120 million in February 2002 from Jeffrey Loria, who now owns the Florida Marlins. The Expos have lost tens of millions over the years.

Baseball is hoping the Expos will fetch more than $300 million in an auction. The league is likely to put the team up for sale this fall and possibly close the deal by year's end, which would give a new ownership group an opportunity to put its stamp on the organization.

The District was chosen over five other locations vying for the Expos, including Northern Virginia, Norfolk, Las Vegas, Portland, Ore., and Monterrey, Mexico. Baseball all but settled on the District at a meeting of its executive council in Milwaukee last week, where the District's bid overwhelmed the competition.

Angelos spoke for about 15 minutes to his eight fellow owners gathered around the conference table at Selig's Milwaukee office, telling them a team in Washington was bad for baseball, bad for the Orioles and bad for the city of Baltimore.

Even though Angelos had some sympathy from owners such as San Francisco Giants owner Peter Magowan and New York Mets owner Fred Wilpon, it became clear to many fellow owners that Washington's wealthy demographics, coupled with the lack of viable alternatives, made it obvious that the Expos will go to Washington.

Yesterday's meeting between Angelos and DuPuy followed a previous meeting between the two last Friday.

Williams, who met with several council members or their staffs yesterday, said he is optimistic that he has enough support on the council to get the stadium built. He said that Cropp emphasized at the meeting that he and other city officials have to sell the virtues of the stadium through a public education campaign.

Williams said the campaign will focus on three things: how the stadium is being paid for; how it benefits the community by adding jobs and businesses; and how it will generate development and improve recreation facilities for children. He said they have to take the message to every neighborhood in the city and detail the benefits for residents.

"We're not building a stadium for people from McLean to come in here," Williams said. "Do we want people from McLean to come in here? Absolutely. But we're not building a stadium just for them. We're building it for the entire region and mostly for our kids and families."

Staff writers John Wagner, Lori Montgomery, Serge Kovaleski and Yolanda Woodlee contributed to this report.

Major League Baseball President Robert A. DuPuy speaks to the media after a six-hour meeting with Orioles owner Peter G. Angelos concerning the Expos' future. Angelos has indicated he could take legal action in the matter.