Roberto Mancini has hit back at Karl-Heinz Rummenigge after the Bayern Munich president again questioned Manchester City's ability to meet UEFA's Financial Fair Play (FFP) regulations.
Rummenigge called on European football's governing body to impose strict sanctions on clubs who fail to meet the criteria for FFP and supports the proposed bans from the Champions League and Europa League.
The German's comments were reported on the eve of the two clubs meeting in a vital Champions League group game at Eastlands - a game Mancini's side must win if they are to have any chance of advancing to the knockout stage.
And the City manager admitted he was frustrated at former Germany striker Rummenigge's decision to once again turn the spotlight on the Premier League leaders' balance sheet.
"I don't understand Rummenigge's behaviour against Manchester City," said Mancini here on Tuesday.
"For six months he talk against us every time for Financial Fair Play and he continues to say he hopes Napoli go through to the second stage. I don't know what's different with us.
"I think Manchester City are working for this FFP for the next two years. But I don't understand what's happening with Rummenigge. Tomorrow, I will ask him."
This month City, owned by the UAE-based Sheikh Mansour, announced annual losses of Â£194.9 million ($304.3m), the highest ever recorded in English football.
Whilst accepting the vast scale of the losses, City officials were adamant it marked a low point in their financial graph and from this point forward, they would be embarking on a significant upward trend.
Thankfully for City, the figures will not be taken into account by the FFP regulations as they fall outside the accounting window.
Meanwhile, a mammoth sponsorship deal with Etihad Airlines, said to be worth Â£35m a year over the next decade, will have begun to impact on City's accounts in 12 months' time.
Mancini, meanwhile, confirmed at his pre-match press conference that he believes it is important Carlos Tevez leaves the club in the January transfer window.
Last month the striker flew to Argentina without the permission of the club, further straining already tense relations after the furore following claims he refused to go on as a substitute during the reverse fixture with Bayern.
Now, Tevez's representatives are reported to have opened talks with AC Milan about a move to Serie A.
"I think that for us it is important to sell him, both for him and the club," said Mancini. "If he has a chance to move, I am happy for him."
Mancini insists there is no rift between himself and Kolo Toure, however, but admits he would consider allowing the centre-back to leave Manchester City at the end of the season.
The manager revealed Toure denied comments attributed to him in a French magazine in which he was reported to have claimed that his position at City was affected by his participation in the Africa Cup of Nations two years ago.
Mancini will take no further action against the player but conceded he would be willing to allow the Ivory Coast star - who has been linked with a move to Paris Saint-Germain - to go if the player wanted regular first-team action.
"I spoke with Kolo and he told me he didn't say anything like this so we have no problem. He spoke to me about it so, for me, now it's finished," Mancini said.
Mancini added: "He is part of our plans for the year, he is a good player and a good guy.
"At this moment he cannot go because we have some injuries and we need his experience.
"If in the summer he asks me, 'Boss, I want to leave because I want to play,' I will respect him as a man and we will talk about this."