Magazine queen Tina Brown's TV debut was abruptly cancelled due to the prospect of war.

CNBC delayed the launch of her new show, Topic A with Tina Brown, within hours of President Bush's televised speech to the nation Monday night.

Brown's first show was supposed to tape Wednesday at CNBC studios in Fort Lee, N.J. for a 9 p.m. air time.

Brown's first show was slated to include "a long list" of celebrity guests to talk about this year's crop of movies. But once it became unmistakable that war with Iraq was imminent, Brown reworked the show to be "more topical," said a source.

"It was going to be up-to-the-moment and she shifted it from entertainment to 'The Challenges of Leadership'," said the source.

The last-minute change was reminiscent of her days at the helm of the New Yorker and Talk magazines -- where she was famous for tearing up nearly completed editions in the final hours for breaking news.

It was not clear why CNBC decided to postpone the show even after she changed the subject to a more war-oriented topic.

Brown did not return calls yesterday.

No new launch date was set for Brown's show.

"Once the war and the rest of the world events take shape, they want to [get the show] right back on the calendar," said a source. "It's really just not prudent to launch the show now."