The Portuguese coach is believed to have been told that he has only won three of his 15 meetings with Guardiola, who is now the manager of Bayern Munich.
"Your statistics are very wrong," BBC Sport quotes Mourinho as saying. "Go and see what happened when I was with Inter in the Champions League semi-final, the King's Cup final with Real in Spain, the Super Cup in Spain.
"Maybe you are right and I am wrong but I don't care. This is not about us, it's about Chelsea and Bayern. If you want to ask questions about Chelsea I am here until four o'clock. If you want to ask questions about Real or Barcelona then I'm not here."
Chelsea go up against Bayern in the European Super Cup in Prague tomorrow.