Earlier this month, it was claimed that Leicester had agreed a £25m deal with Man City for the transfer of the 20-year-old, who has also been linked with West Ham United in this summer's transfer window.
It is understood that the deal is currently being held up by a number of contractual issues, including a potential buy-back clause, but Shakespeare remains confident that a move for the Nigerian will eventually be completed.
"I'm hoping so, but I am like every other manager at the moment. I think we all find it frustrating but it is the current market," Shakespeare told Sky Sports News. "You saw with the Harry Maguire one, we got that done quick - when he is in the door we can announce it.
"At the moment, of course, we are interested in players as most of the Premier League is, but you can see that clubs won't really talk about it until they are over the line."
Iheanacho has scored 21 times in 64 appearances for City, including seven in 29 games during the 2016-17 campaign.