The 44-year-old actor and West End star has apparently signed up for the new series in January, which will see a group of celebrities living together in the famous house in Elstree.
A source told the Daily Star: "John is outspoken and will speak as he finds. He will certainly shake things up."
John, who played Christian Clarke in the BBC One soap, is set to enter the house alongside other rumoured names including ex-WWE star Hulk Hogan, Made In Chelsea's Spencer Matthews, Geordie Shore's Scott Timlin, former TOWIE star Gemma Collins, ex-Hollyoaks actress Stephanie Davis and another former EastEnders star, Danniella Westbrook.
For the new series, the show will take on a theatrical and dramatic theme. The last series of CBB was won by The Apprentice star James Hill.
Celebrity Big Brother: Live Launch, Tuesday 5th January at 9pm on Channel 5
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