England goalkeeper Fraser Forster does not know if he will still be at Celtic when they next play in Europe.
Norwich captain Sebastien Bassong has signed a new two-and-a-half-year contract.
Celtic striker Gary Hooper has dropped a strong hint that he will remain at Parkhead this summer despite interest from the Premier League.
Hooper has been the subject of intense media speculation regarding his future since the turn of the year.
The former Southend and Scunthorpe favourite has yet to commit his future to the Scottish champions, who have offered him a new contract.
Norwich failed with a bid in excess of £7million in January, while Hull City had a smaller offer dismissed last month.
Now Hooper insists his focus is improving on last season's success with Celtic, which included a Champions League victory over Barcelona.
"I want to beat my tally from last season, that's the aim because I've done it every season," he said.
"I also have to get 20 or more league goals because I didn't get it just there, I only got 19.
"I want to play in the Champions League again, get into the group stages and get that feeling again.
"I know I wasn't playing in the game against Barcelona but it was still amazing.
"We also want to retain the title as obviously the league is still our priority."