Iheanacho arrived at the King Power Stadium from Manchester City last summer for a reported £25million but the marquee signing has struggled to cement down a regular starting spot this season.
The 21-year-old, who has been hampered by injuries, has started just three Premier League matches and he has had to settle for substitute appearances for much of the campaign.
Nigeria’s star did manage to open his league account for the Foxes in the 4-1 victory at West Brom last time out and, although impressed with the performance, Rohr has warned the striker needs to play more ahead of the 2018 World Cup.
He told Goal: ‘Kelechi is doing very well. I’m in touch with his coach – Claude Puel – he’s a friend of mine. Let him now play a little bit more and I hope he does because it is not enough playing 20 minutes, even if he scores.
‘He has to play more and I hope now he will have the opportunity to play other games and to be fit for our two friendlies.’
Port Vale boss Neil Aspin is expected to choose from an unchanged squad for the home game against Exeter.