Roberto Mancini blamed sporting director Brian Marwood as he declared himself unhappy that Manchester City have failed to sign any players this summer.
City are the only club in the division who are yet to bring anyone in and Mancini has been frustrated in his attempts to buy Robin van Persie, Daniel Agger and Eden Hazard.
"I am not happy but I won't say anything at the moment," he said. "For this you should talk to Brian Marwood."
City have also failed to sell any of their unwanted players, with Wayne Bridge loaned out to Brighton and Roque Santa Cruz and Emmanuel Adebayor still at the Etihad Stadium.
They had hoped to raise funds and reduce the wage bill before bringing in new players and Mancini added: "I don't know what I should say in this situation because after three months [no one has been signed]."
Mancini believes that, after ending City's 44-year wait to win the league, the club should push on and strengthen further and that a side who came together two years ago would be better with reinforcements.
"I think we have a good team but it is impossible that after two years you did everything well. You need to continue to improve in every way."
Mancini also confirmed that Micah Richards and Gareth Barry are out of Sunday's Community Shield clash with Chelsea.