Bowyer, who is out of contract in June, held initial discussions last summer with Blues over a new deal.
However, talks became protracted and were put on ice. Bowyer claimed after Blues' Carling Cup final triumph over Arsenal on Sunday that he would have to look for a new club.
But McLeish said: "We did speak in the summer but the talks dragged on too long. It ended up that, in terms of our finances for that particular period of time, they had dried up and the goalposts had moved.
"We said 'look, we will address it again at the end of the season'. There are no doors closed on anyone."
Bowyer joined Blues two years ago from West Ham after an initial loan spell and has been a key figure in them becoming established in the Barclays Premier League.
Source: PA
Source: PA