The arrival of Swiss international Timm Klose from FC Nurnberg means that the 24-year old may find opportunities of first-team football limited next season.
Kjaer has one year remaining on his contract with Wolfsburg and he has previously been linked to a Premier League move, with Liverpool and Newcastle United both reported to have been chasing him in recent transfer windows.
The Dane moved to Germany from Palermo in 2010, but Allofs says he could now be set for an exit if he cannot be guaranteed first-team football.
"I have had a chat with Simon Kjaer about his situation at the club and of course, it's not to Simon's satisfaction to not play regular first-team matches," he told German magazine Kicker.
"This may well, in the end, lead him to make a change."