Naismith, 20, remains a Rangers target even though Ibrox manager Walter Smith withdrew his latest offer for the Scotland international.
Jefferies said: "I've resigned myself to the fact Stevie is going. Whether it takes a few days or a few weeks we don't know. If Rangers do agree on a fee then I think he would go there. I would be very happy to have him here for next season but we can't hold the boy back."