Colin Doyle and Robin Shroot are poised to spend time away on loan next season.
Blues' pursuit of Manchester City goalkeeper Joe Hart means Doyle could be available and Norwich are thought to be interested.
Winger Shroot meanwhile will continue his development with a loan spell at Burton Albion.
"Birmingham regard him as a player with a lot of potential, but right now they’re building a squad for the Premier League," said Brewers boss Paul Peschisolido.