Both clubs are expected to strengthen when the market opens at the end of the season, with the likes of Robert Lewandowksi, Gareth Bale and Radamel Falcao being touted as possible players up for grabs this summer.
"I'm sure [City will] come back," the Manchester Evening News quotes Gill as saying. "They've got some ambitious plans on their investment and their academy. That's what the excitement of the Premier League is.
"I'm sure all the clubs who missed out this season will be doing business in the summer, as we will be, with a view to come back all guns blazing next year."