Celtic have opened talks with QPR over a deal for Caulker.
According to a report in The Sun the former Swansea defender could be on his way to a re-union with Brendan Rodgers if the two clubs can agree a deal.
Caulker started his career at Spurs but enjoyed his best form on loan with Rodgers at Swansea and was then involved in £8m transfers to Cardiff and QPR.
After Rodgers left Liverpool the 25-year-old had a loan spell at Anfield but his career has been on a downward spiral due to a range of personal problems.
Last week Rodgers confirmed that he had been speaking with the player about those problems and now it seems that a transfer could be completed.
Moving to Celtic would put the defender firmly in the spotlight but with Dedryck Boyata out injured for another two months Rodgers is short of defensive options with vital Champions League qualifiers approaching.
Caulker has got one year left on his QPR deal and played the last of 14 matches last season on October 28 away to Brentford.
