Roberto Mancini has hit back at the Bayern Munich chairman, Karl-Heinz Rummenigge, for his persistent criticisms of Manchester City and questioned whether it stems from an inbuilt fear about the emergence of the Premier League leaders under the ownership of the Abu Dhabi United Group.

Rummenigge has been one of City's more outspoken critics, along with the Bayern president, Uli Hoeness, and the German club's honorary president, Franz Beckenbauer, because of the problems at the Etihad Stadium when it comes to Uefa's financial fair-play regulations.

In one interview this week he urged Uefa to take "strict penalties" against City and Mancini, preparing for Wednesday's Champions League Group A game against the Bundesliga leaders, made little attempt to conceal his displeasure at what he regards as unfair criticism.

"I don't understand Rummenigge's behaviour against Manchester City," Mancini said. "This has been six months now that he talks against us because of financial fair play. He also says that he hopes Napoli get through to the second stage [instead of City]. I don't know what his problem is with us.

"Manchester City are working for financial fair play for the next two years, so I don't understand what has happened with Rummenigge. There are other teams in Europe that have problems with financial fair play, not just Manchester City. Rummenigge knows his football – he was an incredible player – but I don't why."

Mancini was asked whether it was a sign that the established Champions League clubs were increasingly worried about the impact City could have in Europe over the following years. "Every team is worried about Manchester City because now and in the future we could become one of the top clubs in the world," he said.

Mancini was also unhappy with Aurelio De Laurentiis's recent criticisms of City, when the Napoli president and notoriously outspoken film-maker predicted that Sheikh Mansour and his Abu Dhabi United Group would become bored and look for another "toy."

"Fortunately, Sheikh Mansour is not Italian," Mancini said. "He [De Laurentiis] doesn't know Sheik Mansour. Sheikh Mansour is a good man and we can't think about these stupid comments."

Micah Richards is struggling to be fit for the tie because of a calf problem, while Mancini has confirmed that Aleksandar Kolarov has a groin injury that will keep him out for three weeks but possibly longer. City need to win and rely on Villarreal to avoid defeat against Napoli to go through to the last 16.