Lotus claim Raikkonen will not be at the Spa-Francorchamps on Thursday ahead of this weekend's Belgian Grand Prix "due to illness", but will be at the track for Friday's two practice sessions.
Raikkonen's future has been the source of intense speculation in recent weeks, with a move to Red Bull now seemingly off, and without doubt he would have been grilled by the media on the subject.
The Finn's manager Steve Robertson stated earlier this week the Finn would not be driving for Red Bull next year as talks had broken down.
With rumours rife of a potential return to Ferrari, Robertson further claims the 33-year-old would be happy to remain at Lotus providing he is given assurances about their financial and technical future.
"Lotus hold the key to Raikkonen's future," said Robertson.
"If the team can provide him with the answers he is seeking, which will ensure he has a car that can fight for race wins and the championship, then he will stay."
On track, Raikkonen will be chasing a fifth Belgian GP win on Sunday in a bid to keep himself in the title hunt, with the 33-year-old 38 points behind championship leader Sebastian Vettel.