Wolves have rejected an improved £13million bid from Sunderland for the Scot.
Moxey said: "All parties need to draw a line under this matter, which has dragged on for over a month.
"We need to focus on the season ahead and these disruptions to the squad's preparations are unhelpful.
"We have always said we want to keep our best players. If our valuations of them are not met then they will remain at Wolves.
"But we cannot allow this speculation about their futures to drag on indefinitely up to the closure of the transfer window."