Aides to President Bush and John F. Kerry are sparring over the terms for intelligence briefings for the Democratic presidential nominee, delaying the post-convention overview typically given to the challenger.

Those on Bush's side say the Kerry campaign is insisting on having briefings outside of Washington -- a hardship for top CIA officials during a time of heightened threats -- and is demanding that an unusually large number of Kerry advisers be permitted to participate in the highly classified sessions. Those on Kerry's side say it is the Bush administration that has been slow to deal with the logistics, including security clearances, needed for the briefings.

The result is that at a time when access to sensitive intelligence is more important than ever for national leaders, a skirmish between the White House and the Kerry campaign has postponed the sort of intelligence-sharing that has been standard during presidential races over the past half-century.

On Aug. 2, the Monday after the Democratic convention, Bush's national security adviser Condoleezza Rice called Kerry foreign policy adviser Rand Beers to offer intelligence briefings. When Beers, who was vacationing, returned Rice's call Aug. 5, the two agreed to set up the briefings. But nearly two weeks later, there has been no progress in the discussions.

"We've been given the runaround and bounced around so much that we wonder who's in charge of this," a senior Kerry campaign aide said.

However the matter is resolved, the delay -- an indication that even routine matters have become highly charged in this campaign -- is politically dicey for Kerry, who has been the target of Republican barbs for being slow to receive an earlier briefing on homeland security and for missing briefings given to the Senate intelligence committee. The Bush campaign has designated this week "Intelligence Week," designed to raise questions about Kerry's commitment to intelligence and to portray him as eager to cut intelligence spending during his years in the Senate.

"During the eight years Kerry served on the intelligence committee, he missed 76 percent of the public hearings. And he refuses to disclose to the American people how many classified briefings he missed," said Bush campaign spokesman Steve Schmidt. "John Kerry's campaign trail rhetoric about intelligence reform is disconnected from his record of chronic absenteeism."

A GOP source close to the negotiations said that "the briefing hasn't occurred because Kerry has insisted he doesn't have time for it unless it is done outside of D.C., which is logistically a nightmare for the DCI [director of central intelligence] and [Homeland Security Secretary Tom] Ridge in light of the current threat."

The source, who did not have authorization to discuss the matter publicly and therefore spoke on the condition of anonymity, said the Kerry campaign requested that a "ridiculous number" of aides attend the briefing: Beers, former State Department officials James P. Rubin and Susan Rice, and campaign manager Mary Beth Cahill.

Kerry allies say Rice told them to expect a call from acting CIA Director John E. McLaughlin, but nothing happened until this past Friday, when CIA chief of staff John H. Moseman called. Now, they say, they are waiting for the requested security clearances.

Kerry aides declined to discuss the dispute on the record. "We are just waiting for the White House to grant appropriate clearances," campaign spokesman Chad Clanton said.

A spokesman for the National Security Council, Sean McCormack, declined to discuss the details. "In keeping with past practice, we have offered the briefings, and the briefings have been accepted," he said. "The process is working as it should."

Kerry has received two specific briefings, on the threats to the conventions and to the election, but the briefings under discussion are much broader, worldwide updates involving the most sensitive intelligence.

Over the past 50 years, challengers have traditionally been given worldwide intelligence briefings in the days or weeks after their nominating conventions. In 1976, Jimmy Carter had an intelligence overview in July, before receiving the nomination. Though most candidate briefings have been limited to a single, multi-hour session, Carter received briefings every week to 10 days through the campaign.

According to a paper about such briefings written by the CIA, the preelection sessions for nominees have typically been open to the presidential candidate, the vice presidential nominee and one or two aides, and have been held in various locations. Carter was briefed with Walter F. Mondale and two aides. In 1980, Ronald Reagan was joined by George H.W. Bush and three aides. In 1988, Michael S. Dukakis received the briefing with Lloyd Bentsen, one aide and two members of the House intelligence committee. In 1992, Bill Clinton was joined by Al Gore and two lawmakers.

National security adviser Condoleezza Rice called the Kerry campaign on Aug. 2 to offer intelligence briefings.Kerry adviser Rand Beers and Rice agreed Aug. 5 to set up the briefings. Talks reportedly have not advanced.