Trending @Accenture; Can manager change the hike?

Lets say a scenario. Manager is having a call with the developer. Manager asks what you expectations. At this point developer has got 18% but this is not yet told to developer it has only reached to Manager. The reply from developer for his hike is at least 15%. So my question is can Manager change our hike at this stage from 18 to 15%. (If Manager do this or no we can debate later on this I only want to know if he can)