report by BBC Sport.
The injury forced Terry to miss Sunday's 3-0 defeat by Sunderland and he has also pulled out of England's friendly against France on Wednesday.
A Chelsea source was reported on BBC Sport: "It could be months [until he's fit], although that's the pessimistic view. We don't know the root of the pain."
A Chelsea spokesman said: "John reported for training this morning. He met with club doctors and the medical team and discussed plans to continue seeing various specialists to try to find a solution to the nerve problems he has been experiencing in his right leg."
The injury has been troubling the defender since the end of last season and, despite resting for three weeks between the end of the World Cup and the start of the Premier League season, the problem has not cleared up.
Terry told the Daily Mail : "After games I am in agony and not sleeping at all. I used to play with pain at seven out of 10. Now? It's 10 out of 10. I need to take a few weeks rest, see a couple of specialists and solve the problem."
"It is at a point where I can't carry on with it. I used to be able to make it through games because the adrenaline gets going and you blank the pain out, but now there really is no decision to make."