Ahmed al-Faraj, the brother of Portsmouth owner Ali, says they found the club in a "huge mess" when they first took over.
Previous owner Sacha Gaydamak's regime delivered FA Cup success in 2008 but the club have since struggled to meet their financial commitments and a number of top stars have been sold.
Ahmed said: "The mess was huge when we took over, we couldn't believe it.
"Financially it was unbelievable. We are now addressing this and trying to get everything into place and I promise you we are moving forward.
"Things are improving from now and it will get better, especially financially. We are reducing the debts and stabilising. It is the toughest challenge I have faced, this is not easy.
"If we don't want it we would not have bought the club and we could have waited for administration and got it very cheap and not need to pay all this money.
"I would hope they (the fans) appreciate that and would support our backs and give us a chance to work with them and they will see the results."