Sneijder was instrumental in Inter winning the Champions League and a domestic double last term while he has helped guide the Netherlands to the World Cup final.
Asked if United had made a bid for the Dutchman, Moratti told reporters: "I think so but I don't know. I didn't want to ask too much about it so as not to fall into temptation."
Sneijder has also been linked in the media with a return to Real Madrid after just one season away given former Inter coach Jose Mourinho is now at the Bernabeu.
One man who could definitely be going to Real is Inter right back Maicon while striker Mario Balotelli is also the centre of transfer speculation.
"I still haven't received a good enough offer for even one to leave. We will see," Moratti added.
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