According to the agreement, Barcelona must pay €2.8 million to RB Leipzig as part of the deal that brought Olmo, 27, to the club last summer. Additionally, there is a clause that requires another €4.2 million to be paid if certain conditions are met in the near future.

Olmo's first season at Barcelona was complicated by several registration issues. Now, Williams is requiring assurances that he won't face similar problems if he joins the club.

Barcelona's situation is causing delays in the transfer negotiations, and it remains to be seen how the club will proceed with the deal.