Everton have yet to match Swansea's £50m valuation for the 27-year-old Iceland international.
"We're at a critical stage and hope it's going to be resolved as soon as possible," said Clement.
"They [the club's owners] understand the pros and cons of doing it earlier rather than later.
"I know for sure they have the best interest of the club in mind.
"Clearly with each day goes by you get a little bit more frustrated because you don't know if you're going to have the player or if not, will you be able to get in the targets you want."