Celtic boss Ronny Deila says keeping his best players will take priority over acquisitions in the transfer window.
Chelsea striker Fernando Torres is understood to be set for a return to Atletico Madrid, according to Sky sources.
Reading have confirmed the signing of 21-year-old Hope Akpan from League One side Crawley.
The midfielder, who joined Crawley from Everton in 2011, has agreed a three-and-a-half year contract.
Reading manager Brian McDermott told the club website: "I'm delighted to have signed Hope, we have known all about him for a very long time.
"He has a great pedigree coming through the ranks at a top Premier League side in Everton.
"There were a lot of clubs in for him during this window, but once he heard of our interest this was the only place he wanted to play. He's 21 and is a player we feel can play at this level."
Reading said the deal is subject to final ratification of all the paperwork from the football authorities, but they expect that to be a formality.