AS Monaco are refusing to sell Benoit Badiashile to Chelsea before they have his replacement signed.
The two clubs have agreed a fee for the France international defender, who has been left out of ASM's matchday squad this week.
Badiashile is waiting for ASM to find a replacement for him ahead of completing his move to London.
And the transfer is close to now being finalised with ASM in talks with Royal Antwerp for Willian Pacho.
Pacho is also wanted by Rangers, though Monaco are confident reaching terms.