Oliveira is co-owned by Spanish sides Real Zaragoza and Real Betis and the two clubs have accepted a bid of around €15million.
“After considering my family, I have decided to accept this opportunity,” the 29 year old told AS.
“Leaving La Liga is difficult but this move is very important for me. Zaragoza and Betis had also pushed for this deal to go through so everyone will benefit from this.
“I hope the Betis supporters will understand my perspective.”
