QPR lost £65.4million last season, when they were relegated from the Barclays Premier League, while their debt almost doubled to £177million.
Their financial situation puts them at risk of facing fines totalling tens of millions of pounds due to the Football League's financial fair play rules.
Fernandes said in a statement on the club's website: "Relegation wasn't part of the plan and it has cost us financially and emotionally, but I and my fellow shareholder are fighters. We are committed and here for the long term."
He said that having built up the squad there was no need to invest more money - and indeed that a number of players could be sold.
Fernandes also insists that promotion back to the Premier League this season is not vital.
He added: "Achieving promotion this season is not critical to our long-term strategy, but it remains our short-term goal.
"If we fail in our bid for promotion, the support is there and there is no need for any more advances to build a squad.
"We are now in a position where we can work with what we have, and raise capital to invest in the squad by selling players who are not part of the manager's plans.
"We would like to reassure the QPR supporters that our commitment is unwavering and we remain passionate about our club."
Fernandes also stressed that the club's debt was mainly in the form of shareholder loans.
"The debt in the club is owed TO the shareholders BY the shareholders," he said.
QPR manager Harry Redknapp has also revealed that he has been assured that the owners are at Loftus Road for the long haul.
He said: "I spoke with the chairman and the rest of the board and they are very, very committed to the club and the long-term of the club. The club is in great hands.
"They have given me great support since I have been here. It doesn't make my job any harder. The aim is to try to get promoted - we know it is not going to be easy but that's the aim this year.
"But whatever happens they are here for the long haul. They are looking to build a stadium, training ground, they want to take the club forward. I don't think QPR could be in better hands than what it is at the moment.
"I think you will find there are lots of clubs who have got financial problems but as far as I know it is the shareholders' money. They are not leaving the club in a situation where if they pull the plug, the club is going down the drain. That's not going to happen here."