The club announced earlier this month that their debt had risen to £716.5million.
But Gill is upbeat over their financial situation, saying they had a bid for Karim Benzema rejected last summer.
“Without doubt,” said Gill. “We used £15million to buy Antonio Valencia and we have well over £100m in the bank sitting there.
“People look from the outside and say Alex has been under pressure. I think everyone who has dealt with Alex or seen him in the press knows he will not compromise what he wants to do for this club.
“If I went to (joint board chairman) Joel Glazer and said ‘Alex wants a particular player, can we have the money?’ The answer would be an unequivocal yes.
“They have demonstrated it (with Benzema). We didn’t get Benzema but we did offer 35m euros.”
Gill also insisted the Glazer family would not sell Old Trafford or the club’s Carrington training ground.
“This is a long-term thing,” he said. “They bought (American football team) the Tampa Bay Buccaneers in 1995 and 15 years later, they still own that – they are in it for the long term.
“All the actions they’ve taken, whether it be investing in the infrastructure, whether it be putting more money into looking at Carrington, into players… it strikes me it’s all long-term views.”
He added on the chances of Carrington being sold and leased back to the club: “I am 100% convinced that will never happen under Glazer family ownership.
“The sale and leaseback opportunity within the bond document is done for financial and tax planning. Manchester United Limited continue to have complete control of Carrington.”
