WASHINGTON, Oct 26 (Reuters) - The U.S. government's main disaster-response agency apologized on Friday for having its employees pose as reporters in a hastily called news conference on California's wildfires that no news organizations attended.

The Federal Emergency Management Agency, still struggling to restore its image after the bungled handling of Hurricane Katrina in 2005, issued the apology after The Washington Post published details of the Tuesday briefing.

"We can and must do better, and apologize for this error in judgment," FEMA deputy administrator Harvey Johnson, who conducted the briefing, said in a statement. "Our intent was to provide useful information and be responsive to the many questions we have received."

No actual reporter attended the news conference in person, agency spokesman Aaron Walker said.

A spokeswoman for Homeland Security Secretary Michael Chertoff, who has authority over FEMA, called the incident "inexcusable and offensive to the secretary."

"We have made it clear that stunts such as this will not be tolerated or repeated," spokeswoman Laura Keehner said. She said the department was looking at the possibility of reprimanding those responsible.

The agency had called the briefing with about 15 minutes notice as federal officials headed for southern California to oversee and assist in firefighting and rescue efforts. Reporters were also given a telephone number to listen in on but could not ask questions.

But with no reporters on hand and an agency video camera providing a feed carried live by some television networks, FEMA press employees posed the questions for Johnson that included: "Are you happy with FEMA's response so far?"

According to Friday's Post account, which Walker confirmed, Johnson replied that he was "very happy with FEMA's response so far."

He also said the agency had the benefit of "good leadership" and other factors, "none of which were present at Katrina." Chertoff was head of the Homeland Security Department during Katrina.

FEMA's administrator during Katrina, Michael Brown, resigned amid widespread criticism over his handling of the disaster, despite U.S. President George W. Bush's initial declaration that he was doing a "heck of a job."

E-mails between Brown and his colleagues over the course of the storm revealed a preoccupation with his media image, including his declaration, "I am a fashion god."

FEMA is reviewing its press procedures and will make changes to ensure they are "straightforward and transparent," Johnson said on Friday.