Neil is to take over as chief executive of the right-wing political magazine with immediate effect.
His appointment follows weeks of scandal at the magazine, which at the weekend saw editor and Tory MP for Henley-on-Thames Johnson sacked from the Shadow Cabinet.
He was sacked after lying to Conservative Party leader Michael Howard about an extramarital affair with Spectator columnist Petronella Wyatt.
The story was front page news in a number of weekend newspapers and the story continued to run yesterday.
Speculation in several papers suggested that Johnson was fighting to hang on to his job at the magazine after his affair with Wyatt, which the MP had denied.
A report in The Times yesterday said that Sir Frederick and Sir David Barclay, who acquired The Spectator as part of their takeover of the Telegraph Group, were "at the end of their tether" with Johnson.
The billionaire brothers are committed Roman Catholics, who are said to have been upset by the press stories.
Johnson took over the editorship of The Spectator from Frank Johnson in July 1999 and has helped push the magazine's circulation up from 58,000 to 65,000.
Sources this morning have said the decision to move Neil in as chief executive had been long planned and was a business decision and unrelated to its editor's activities.
It is the second scandal to hit the magazine this year Kimberly Fortier, publisher of The Spectator was the centre of tabloid attention after her affair with home secretary David Blunkett was exposed.
The third Spectator affair to come to tabloid attention was former 'Today' editor and now Spectator writer Rod Liddle, who left his wife for the magazine's editorial assistant Alicia Monckton.
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