The Bush and Kerry campaigns have concluded a final agreement for three presidential debates and one vice presidential debate, according to GOP sources who say details of a "signed deal" will be announced late Monday.

Secretary of State James A. Baker III (search) has been leading the negotiations for Bush, while Kerry has been represented by attorney Vernon Jordan (search).

The debates had been planned to be held during a two-week period beginning Sept. 30 at the University of Miami in Coral Gables, Fla., with following face-offs on Oct. 8, a Friday night, at Washington University in St. Louis and Wednesday, Oct. 13, at Arizona State University in Tempe. All the debates will begin at 9:00 p.m. EDT.

The nonpartisan Commission on Presidential Debates (search) selected the dates and places. Devenish said Baker told the Bush staff no deal was reached.

According to preliminary information, the first debate will focus on foreign policy, the third debate on domestic matters. The topic of the middle debate, which had been under dispute, is still undecided.

Commission members envisioned the second debate featuring undecided voters asking questions of the candidates. That would be an unusual format, and Bush campaign officials have said they don't think the commission can guarantee the questioners would really be undecided, rather than secret Kerry supporters, and they don't think very many undecided voters are left anyway.

The agreement also calls for one vice presidential debate on Oct. 5 between Vice President Dick Cheney (search) and Sen. John Edwards (search), Kerry's running mate.

The co-chairmen of the debate commission told representatives for Bush and Kerry on Wednesday that they must act immediately to finalize details for the debates that are quickly approaching.

The Kerry campaign agreed last month to the commission's proposal for venues, dates and moderators for three debates involving the presidential candidates and one for the vice presidential candidates. However, the Bush campaign would not commit to the proposal.

With a guaranteed television audience of tens of millions of people, the debates could have a major impact because of the closeness of the race and the voters who still count themselves as undecided.

In a poll by the Pew Research Center (search), 29 percent of those surveyed said the debates would matter in deciding how they would vote. Some 68 percent said their minds were already made up.

Those undecided voters could make a huge difference. According to a Nielsen survey, 46.6 million people watched the first debate between Bush and Al Gore in 2000. The second and third debates drew audiences of 37.6 million and 37.7 million, respectively.

The debates between Bush and Gore lasted 90 minutes each. Their running mates debated once in the month of October.

Fox News' Kelly Wright and Wendell Goler and The Associated Press contributed to this report.