Acting chairman Peter Pannu questioned the success of some of McLeish's signings ahead of Saturday's 5-0 mauling by Manchester United at Old Trafford, while bids to bring in Robbie Keane and Kenny Miller have failed.
However, the Blues manager remains focused on turning around a 2-1 deficit against West Ham in the Carling Cup semi-final at St Andrew's.
"We are still trying to enhance the squad - we just have to wait and see," said McLeish.
"If it goes to the wire, it goes to the wire, but I am trying to help the lads to improve for the second half of the season.
"It has been frustrating in one or two situations but I will put it to bed for 24 hours and get this semi-final out of the way."
He added: "As for Peter's comments, we are not getting involved in those comments. We are only talking about the Carling Cup."
McLeish is confident he will receive a positive reaction from his players after the defeat against the Red Devils.
He said: "We are looking forward to it. Hopefully the outcome is fantastic for us in terms of reaching the final itself.
"We know we've got a tough game against West Ham, but we are at St Andrew's, the players are up for it, and we've worked hard over the last couple of days to prepare.
"I don't want the players to leave anything inside the dressing room and to come off the pitch having given everything.
"It would be a marvellous feeling to get to Wembley. It would be a great honour and prestigious to do that and we are capable of doing that.
"There is no doubt they are capable of winning this game on Wednesday night."