Sky sources understand the fine will be payable over three years although City are reportedly contesting the sanctions.
And with City deciding to appeal, the case will now be handed to a panel whose non-negotiable decision will be final.
Full confirmation of the fine and conditions imposed is expected by the end of the week or early next week.
The risk of not agreeing with this decision is that the club could face even stiffer penalties from the CFCB's (UEFA's club financial control board) adjudicatory panel.
The reduction in the size of their Champions League squad however, from 25 to 21, will hit the club hardest, with City having to ensure that there are still eight locally-trained players in their squad.
City boss Manuel Pellegrini refused to give his opinion regarding the sanction, saying: "When it is official news of UEFA we can analyse what happens with
the team. In this moment we don't know what happens."
UEFA president Michel Platini said recently that he did not expect any club to be excluded from next season's Champions League for breaching spending limits.
French giants Paris Saint-Germain are one of eight other clubs currently under investigation for breaking UEFA's financial rules.
French newspaper L'Equipe has reported that PSG are facing even stiffer penalties from UEFA than City.
Like City, they will be fined and see their Champions League squad reduced. But they will also have restrictions imposed on their wage bill and their transfers.
Arsenal boss Arsene Wenger is among those to have previously called for harsh sanctions on clubs that break Financial Fair Play rules.
He said last week: "There are rules to apply for Financial Fair Play. If you don't respect them, you have to apply the rules.
"One of the rules is that normally you should be banned for the excess of the financial amount that is not justified, that is if you are £100m overboard, you should be punished for £100m of your wages bill in the Champions League.
"I want to see that respected, if that is not respected, then the financial fair play will have problems to be respected in the future because everyone will just not consider it at all.
"If it is not respected, of course we will feel let down."