Guarin already has a four-year contract with the San Siro outfit signed should they activate the clause, something that 25-year-old believes will happen.
"I feel that I will stay at Inter for all four years of the contract I signed," the midfielder told FCInter1908.it on Thursday.
"I still have to wait [for confirmation], but I feel very confident. Inter is a club that enchants me, and my family is thrilled with the city of Milan.
"I have recovered from my injury in a positive way, meaning that when I returned to the camp I was able to give a good intensity to my performances."