Mourinho has been linked with returns to both Chelsea and Inter in recent weeks as his future in Spain remains shrouded in doubt, and Karana has conceded the 50-year-old's departure will force him to consider his own plans.
“The day that Mourinho decides to leave, I will also decide my future,” Karanka told a press conference.
“I am delighted with him and the rest of the coaching staff, and I am not planning anything at the moment."
Looking ahead to his weekend's trip to Real Zaragoza, Karanka has urged his side to pick up their good form from where they left off prior to the international break.
“They are in a difficult situation and we come from a week of internationals. We were on a good run until the break," the former defender explained.
"The team is doing very well and the decisive part of the season is starting. We have to maintain our form from before the break. Fortunately we have seen no serious injuries to our players, unlike last time.
“The important thing is that we win and continue the run of victories we were on before. The team is good and we are entering the key part of the season. We have to keep on track.”