WASHINGTON (CNN) - The White House on Thursday dismissed a critical book on the Bush administration by former Press Secretary Scott McClellan as the work of a "disgruntled" former employee.

President Bush is unlikely to comment on the book, in which McClellan charges his former colleagues allowed propaganda and spin to overwhelm the truth, current Press Secretary Dana Perino said in a written statement.

"Scott, we now know, is disgruntled about his experience at the White House," Perino said. "For those of us who fully supported him, before, during and after he was press secretary, we are puzzled. It is sad - this is not the Scott we knew."

McClellan's new memoir, "What Happened: Inside the Bush White House and Washington's Culture of Deception," is scheduled for publication Monday.