It is a case in which words that are literally true are used to convey a false impression; analysis of whether or when such behavior constitutes lying is a long-standing issue in ethics.
British newspaper The Sunday Times has defined it as "an on-the-record statement, usually made by a politician, repudiating a journalist's story, but in such a way as to leave open the possibility that it is actually true".
[1] The Washington Post editor Ben Bradlee "is credited with coining the phrase non-denial denial to characterize the evasive Oval Office answers to questions.
"[2] The phrase was popularized during the Watergate scandal by Bob Woodward and Carl Bernstein in their 1974 book All the President's Men, in reference to evasive statements and equivocal denials by then-Attorney General John N.
[3] William Goldman's screenplay for the 1976 film adaptation put the phrase into the mouth of Ben Bradlee and used it for dramatic purpose.
[5] Another example, characterized by the BBC as a "non-denial denial", was provided by Tony Blair, who was interviewed in 1997, just before the general election, by the British newspaper Evening Standard.