Trevor Birch, who added that the salary levels of several highly-paid players may be deterring a potential sale of the south coast club, said Pompey were paying the price for a series of supposed benefactors taking over and then not covering the gap in income.
Birch, speaking at the Soccerex conference in Manchester, said: "The Premier League is one of the most successful exports we have but if you move down the leagues it becomes a bit of a catastrophe.
"The Championship is a scene of carnage with clubs pursuing the Holy Grail of promotion, losing between £5million and £10million a year and a third of them spending over 100% of turnover on wages.
"That's why the Championship are looking to bring in financial fair play rules.
"Crowds are down, sponsorship levels are down and clubs are suffering on corporate hospitality as well, down by 20-30% in certain areas, but if you are successful on the pitch you will be successful off the pitch as well."