But the Spain international insists nothing has ever happened behind either man's back.
"We've had our differences, but we have said things to the face and our relationship is not as damaged like people say," revealed Ramos.
"There is a super professional relationship, good in every way. It would be very awkward if our problems weren't out in the open, because we are at a very delicate stage of the season."
Ramos also insisted he did not regret the Mesut Ozil shirt incident earlier this season.
"I do not regret it. I've already explained that there is a better feeling with Mou."
Ramos was referring to a game earlier this season when he wore Ozil's shirt under his own after his teammate had been hooked by Mourinho at halftime.