▪Midfielder, 21, was star man in Copa Libertadores win and has been in talks with La Liga giants since end of 2017.
Gremio reported the Nou Camp giants to Fifa when Arthur was pictured a Barcelona shirt — and the La Liga leaders were forced into an apology.
But Marca report a deal is edging closer with a meeting arranged for this weekend.
It is a complicated transfer, with the player's rights being owned by three different parties.
Gremio own 60 per cent — and have set his release clause at £50million — while the rest is split evenly between businessman Celso Rigo and Arthur's family.