Chelsea and Barcelona have been in talks in the last few days over the signing of striker Pierre-Emerick Aubameyang.
Those talks - which have gone late into the night - have so far failed to find an agreement.
The deal under discussion is thought to be worth between £15m and £25m. Chelsea want to include Marcos Alonso in the package, while Barcelona want straight cash.
Barcelona want the money to help enable them to register Jules Kounde.
Barca have been interested in signing Alonso this summer, with one source claiming that has cooled given their issues in registering their new signings.
Aubameyang continues to train as normal, with Barcelona playing away at Real Sociedad on Sunday night.
Discussions between Chelsea and Barcelona are ongoing and there is a willingness from both clubs to get a deal done.
Aubameyang moved to Barcelona on a free transfer from Arsenal in January. He has three years left on his contract.
Although Thomas Tuchel has been reluctant to talk about Aubameyang in public he is keen to work again with a player who scored 79 goals for him in two seasons at Borussia Dortmund.
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