Skysports.com understands that Stoke City have made a double bid for Scott Dann and Cameron Jerome.
It is believed the Potters have lodged an offer of £16million for the pair, and are now awaiting Birmingham's response.
Birmingham are understood to be considering the offer, with both players keen to seal a quick-fire return to the top flight following the Blues' relegation, although it does not look like being enough to tempt them into selling both.
Stoke made their first move for Dann earlier this month - as revealed by skysports.com - and they are looking to steal a march on the likes of Arsenal, Liverpool and Aston Villa who are also considering a summer move.
The Potters, who will embark on a Europa League campaign next season, are also looking to land Dann's team-mate Jerome.
Jerome has already been the subject of a failed bid from Bolton this summer, but now Stoke have made their move as Tony Pulis hopes to soon complete his first signing of pre-season.