Journalists and the U.S. military have agreed to try a new format for the daily war briefing that provides for a 30-minute televised portion followed by a "background" session with military spokesmen.

The new format was started Saturday, three days after Lt. Col. Mike Gallagher, the command's media director, agreed to extend the briefings beyond 30 minutes.He insisted, however, that the additional period not be televised and that officers would speak only on background, meaning all information they provide would be attributed to "military sources" rather than to named officials.

Following the Saturday briefing, U.S. military officials demanded an apology from Cable News Network because it broadcast a claim that the commander of American forces in the gulf - Gen. H. Norman Schwartzkopf - had ordered CNN to stop televising a news briefing.

Military spokesmen noted that Schwarzkopf had not ordered a stop to the broadcast, and that the cutoff of TV cameras after 30 minutes was part of an agreement worked out among members of the media and accepted by U.S. officials.

Under the new arrangement, Pentagon spokesman Pete Williams said, televised coverage of the news briefing will be limited so the rest of the briefing could be on background and the briefers would be freer to give out information.

The idea came from media representatives after Schwartzkopf complained the briefings were too "messy," Williams said. He did not explain.