"We have agreed a fee in principle with Birmingham City and Robbie is talking to them as I speak," Adams told Leicester's official website.
"He just needs to agree personal terms and I can then see the move going through.
"It's very disappointing from our point of view because ideally we would like to keep our better players.
"But Robbie has publicly expressed a desire to remain in the premier league.
"Our financial situation is also well documented and as a result we have to offload players."