But he cast doubt over his long-term future after his side ended their European adventure with a 6-1 defeat by Barcelona on Wednesday.
When asked whether he expected to still be at Celtic when their next Champions League campaign begins, Forster said: “I don’t know. There’s a lot of time between now and then.
“It is hard to say either way. Obviously I’m contracted to Celtic and I will be for the foreseeable future, I imagine.
“It is just important that I do the best I can do, whether it is for Celtic or whoever.
“I’ve just got to be positive and do everything I can between now and the end of the season to try and force my way on to the plane with the England squad."