Barcelona has told Chelsea that they must pay £21 million for striker Pierre-Emerick Aubameyang, who they signed on a free transfer seven months ago.
Chelsea held talks with the LaLiga giants over the weekend and are ready to make an offer this week.
Barcelona target Marcos Alonso has been discussed as part of negotiations to head in the opposite direction.
The ex-Arsenal star has scored 11 goals in 13 starts since joining the Catalan giants in January but has now fallen down the pecking order following the signing of Polish striker Robert Lewandowski.
The Blues are chasing down Aubameyang to help them in attack after Romelu Lukaku re-joined Inter Milan on loan and Timo Werner sealed a return to RB Leipzig for £25million.
Boss Thomas Tuchel is keen to link back up with the 33-year-old forward after their positive relationship at Borussia Dortmund and would like to add a proven goal-scorer to his Chelsea ranks.
