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.