No details have been publicly released and it is believed the club still have to seek planning permission, but the relocation appears to be heading for Ministry of Defence-owned land on the edge of the city.
Pompey, whose current, outdated stadium can only house just over 20,000 fans, are looking to build a new 36,000 all-seater facility, despite previous chairman and owner Milan Mandaric's efforts over the past seven years to redevelop the current site.
Franco-Russian businessman Sacha Gaydamak bought out Mandaric's remaining shares earlier this year after paying around £16 million for a half-stake in the club in January 2006. Mandaric has since taken over at Championship club Leicester.
Gaydamak, who is rarely seen around the club except at matches, already has plans for a new training ground at nearby Fareham to replace Pompey's current accommodation at Eastleigh - deep in the territory of local rivals Southampton.
His financial backing has helped manager Harry Redknapp rebuild his team this season from perennial relegation-strugglers to a side on the cusp of qualifying for next season's UEFA Cup competition.
And he is believed to have told Redknapp there will more cash for further strengthening of the squad this summer.
Portsmouth's chief executive Peter Storrie and manager Harry Redknapp will attend Wednesday's launch at a London hotel along with players including Sol Campbell, David James, Dejan Stefanovic and Gary O'Neil.
Gaydamak's name does not appear on the guest-list but sources close to the club believe that he will be in attendance.