Sweden striker Ibrahimovic has just one year left on his contract at the San Siro and a number of clubs including Chelsea, Barcelona, Real Madrid and Manchester United are keen on securing his services.
United accepted an £80 million offer for Cristiano Ronaldo from Real Madrid last week, while Franck Ribery is valued at €70 million by his club, Bayern Munich.
"If it is true that Bayern Munich have placed a €70 million tag on Ribery, then I will need to ask a minimum of €90 million (for Ibrahimovic)," Moratti told Gazzetta dello Sport.
Moratti and his Barcelona counterpart, Joan Laporta, held talks last week about a potential transfer, but they broke down before a fee could be decided.
However, Moratti insists that Inter have not received an official offer for the striker.
"If we are talking about Barcelona I think Laporta is far away from the mega-investment policy that Real Madrid have made so far," he said.
"No offer has been made for Ibrahimovic. Perhaps it will arrive tomorrow or it will come from another place (not Barcelona), but as of today, there isn't one."
New Chelsea manager Carlo Ancelotti is in the market for a striker and Serie A's top scorer would fit the bill. Moratti, however, is hopeful that the 27-year-old will stay in Milan.
"I reiterate that I would gladly keep Ibrahimovic," said Moratti. "Ibrahimovic is at Inter and Ibrahimovic is the best, in my opinion."