“Ljunberg’s participation against Iceland is highly doubtful,” a statement published on the Swedish FA’s website said.
The Arsenal midfielder limped off early in the second half of Sweden’s 2-0 victory over Spain in Saturday’s Euro 2008 qualifier.
Ljungberg will undergo tests on Monday, the results of which will determine whether or not he travels to Reykjavik for Wednesday’s match.
If he proves unfit, Ljungberg is to return to Britain for further tests with Arsenal’s medical team.
Stefan Ishizaki is on standby to replace Ljungberg.