WASHINGTON (CNN) -- The White House Wednesday said it was "puzzled" by a former spokesman's memoir in which he accuses the Bush administration of being mired in propaganda and political spin and at times playing loose with the truth.

Former White House spokesman Scott McClellan blasts President Bush and advisers in a new book.

In excerpts from a 341-page book to be released Monday, Scott McClellan writes on the war in Iraq that Bush "and his advisers confused the propaganda campaign with the high level of candor and honesty so fundamentally needed to build and then sustain public support during a time of war."

"[I]n this regard, he was terribly ill-served by his top advisers, especially those involved directly in national security," McClellan wrote.

White House spokeswoman Dana Perino called McClellan's description of his time at the White House "sad." Read excerpts from the book »

"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 former White House colleagues had harsher reactions to McClellan's book.

Frances Townsend, former Homeland Security adviser to Bush, said advisers to the president should speak up when they have policy concerns.

"Scott never did that on any of these issues as best I can remember or as best as I know from any of my White House colleagues," said Townsend, now a CNN contributor. "For him to do this now strikes me as self-serving, disingenuous and unprofessional."

Fox News contributor and former White House adviser Karl Rove said on that network Tuesday that the excerpts from the book he's read sound more like they were written by a "left-wing blogger" than his former colleague.

Rove declined to comment to CNN after the Fox News interview.

In a brief phone conversation with CNN Tuesday evening, McClellan made clear that he stands behind the accuracy of his book. McClellan said he cannot give on-the-record quotes yet because of an agreement with his publisher. Watch further details emerge from McClellan's book »

Another former Bush aide-turned-critic says the reaction to McClellan's book by his former colleagues has a familiar ring to it.

"They're saying some of the exact same things about McClellan they said about me," Richard Clarke, the former White House counterterrorism chief, told CNN.

Clarke left government in 2003. The following year, he accused President Bush of ignoring warnings about the September 11, 2001, attacks on New York and Washington and of using the attacks to push for war with Iraq.

But Clarke gave McClellan little credit for speaking out now.

"I think the difference with McClellan's book is he's now telling us something we all know -- that the war with Iraq was a disastrous war [and] was sold with deception. It's a little different when you say something as I did and a few other people did four or five years ago, when the war was popular and when we were unpopular for saying what we said."

Besides his criticism of how the administration handled the run-up to the Iraq war, McClellan also sharply criticizes the administration on its handling of Hurricane Katrina and its aftermath in the book.

"One of the worst disasters in our nation's history became one of the biggest disasters in Bush's presidency," he wrote. "Katrina and the botched federal response to it would largely come to define Bush's second term."

Early in the book, which CNN obtained late Tuesday, McClellan wrote that he believes he told untruths on Bush's behalf in the case of CIA agent Valerie Plame, whose identity was leaked to the media.

Rove and fellow White House advisers Elliot Abrams and I. Lewis "Scooter" Libby were accused of leaking the name of Plame -- whose husband, former U.S. ambassador Joseph Wilson, had gone public with charges the Bush administration had "twisted" facts to justify the war in Iraq.

Libby was convicted last year of lying to a grand jury and federal agents investigating the leak. Bush commuted his 30-month prison term, calling it excessive. At the time, McClellan called the three "good individuals" and said he spoke to them before telling reporters they were not involved.

"I had allowed myself to be deceived into unknowingly passing along a falsehood," he wrote. "It would ultimately prove fatal to my ability to serve the president effectively."

McClellan wrote he didn't realize what he said was untrue until reporters began digging up details of the case almost two years later.

A former spokesman for Bush when he was governor of Texas, McClellan was named White House press secretary in 2003, replacing Ari Fleischer. McClellan had previously been a deputy press secretary and was the traveling spokesman for the Bush campaign during the 2000 election.

He announced he was resigning in April 2006 at a news conference with Bush.

"One of these days, he and I are going to be rocking in chairs in Texas talking about the good old days of his time as the press secretary," Bush said at that conference. "And I can assure you, I will feel the same way then that I feel now, that I can say to Scott, job well done."

CNN's Ed Henry contributed to this report.

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