WASHINGTON —  First came the leak. Now comes the book.

Former Ambassador Joseph Wilson (search) is writing a memoir about his diplomatic career and the leak that exposed his wife as a CIA employee and led to a major investigation.

Carroll & Graf Publishers, which announced the deal Wednesday, would not say what Wilson would be paid for "The Politics of Truth," due on bookshelves next spring.

"We made an offer, and he was happy with that," spokeswoman Karen Auerbach said.

A statement from the publisher promised Wilson "will provide an unabashedly candid and truthful assessment of the United States' involvement in the world."

The Justice Department has begun a criminal investigation to determine who in the Bush administration leaked the identity of Wilson's wife, Valerie Plame (search), an undercover CIA operations officer.

Before Plame was outed in the press, Wilson had accused the White House of manipulating intelligence to exaggerate the threat from Iraq's former president, Saddam Hussein. Wilson has suggested his wife's name was leaked as retaliation for his views.

Auerbach said talks with Wilson began during the summer, and an agreement was reached the week before the leak controversy broke in newspapers.

In an interview Wednesday, Wilson said he doesn't know the identity of the leaker and trusts the Bush administration will conduct a thorough investigation.

"I have every confidence that the president of the United States shares my and everybody's concern when national security assets are exposed in the media," he said.

Wilson, a career diplomat from 1976 to 1998, was tapped by the CIA (search) in 2002 to go to Niger (search) to investigate a report that Iraq had sought uranium from that country to reconstitute Hussein's program to develop nuclear weapons.

Wilson reported that he found no evidence to support the allegation, and expressed dismay when it ended up in President Bush's State of the Union address in January.