Poyet told BBC Sussex: "It's not in our hands and we cannot finalise things so we need to keep waiting unfortunately."
The Uruguayan also confirmed veteran utility player Gary Hart is set to sign a new one year deal.
The first team squad fly to Portugal to begin a pre-season tour this week, with Poyet saying he has yet to make a decision on current trialists Erik Midtgargen from Norway and Felipe Morais from Portugal.
Source: BBC Sport
Source: BBC Sport