It would leave the team short and wreck my chances of finishing the Ashes tour.'
Lee hopes to begin bowling again soon if his side strain has sufficiently healed, but it will not be in Australia's tour match against Northampton over the next three days.
He said he is now aiming a return in the fourth Test.
'You could be out for 10 to 12 weeks. The way I'm looking now I'm focused on aiming for the fourth Test and making sure I'm right.
'A batsman can come straight back in and bat but a bowler has to build up their pace again. So I need a week and a half or two weeks to get myself ready.
'The way I've planned it is I hope to start bowling in the next day or two, which will leave me exactly two weeks of bowling to get up to full pace again.'