Bayer Leverkusen are preparing a bid for Celtic defender Efe Ambrose, according to the Glasgow Evening Times.
The local paper believes the Bundesliga side have signalled their intentions that they will bid £1.5million for the 27-year-old.
The centre back has just one year left on his contract at Celtic Park and Leverkusen have made the Nigerian international a priority signing this summer.
Ambrose is not currently with the Celtic squad as they continue their pre-season training. He has had issues getting a work permit to travel to Slovenia and manager Brendan Rodgers has said that the club are still waiting on confirmation on when the Nigerian will be allowed to travel to Maribor to join up with the squad.
The Celtic boss has commented in recent days that a new centre back is needed with Dedryck Boyata and Jozo Simunovic injured, and contract talks with Charlie Mulgrew still ongoing.
Rodgers may want to bring in a new defender before he allows Ambrose to leave the club.