Birmingham are in talks with Tottenham as they attempt to strike a deal to bring Robbie Keane to St Andrew's.
Blues boss Alex McLeish has made it clear signing a quality forward is his number one priority during the current transfer window.
He has been linked with Keane, Cardiff's Jay Bothroyd and - on loan - Liverpool's Ryan Babel.
But 30-year-old Keane is the player City are actively pursuing, although the midlands club are adamant reports he has already undergone a medical are wide of the mark.
It is not clear whether any deal for the Republic Of Ireland international would be permanent or a short-term arrangement.
But sources close to Birmingham indicate a full-time move - in the region of £6million - could be a possibility.
Keane has slipped down the pecking order at White Hart Lane and is desperate to play regular first-team football. He has also recently been linked with a move to relegation-threatened West Ham.
Birmingham's lack of goal power has been the main reason why they have been locked in a survival battle during the first half of the season.
Midfielder Craig Gardner is the top scorer with just five goals and McLeish has become frustrated by his side's inability to convert their chances.
McLeish spent £6million in the summer on Serbia international Nikola Zigic but the former Valencia player is still coming to terms with the demands of the Premier League.
Cameron Jerome has failed to reproduce the form which brought him 11 Premier League goals last season while Kevin Phillips is now at the veteran age of 37.
Keane spent the second half of last season on loan at Celtic.