Mazzarri is halfway into a two-year deal at the Serie A giants, whose chief Piero Ausilio said a contract offer was on the table.
The former Napoli coach, whose side finished their campaign with a 2-1 loss at Chievo on Sunday, said he was ready for next season.
"Not continuing with Inter? I already have a contract," Mazzarri told a news conference.
"Last year at Napoli mine was set to expire and I had the best season of my career. I wouldn't change anything if not extend it, because I already have one.
"Next season I'll give my all for these colours, beyond any extension."
Mazzarri insisted a contract was 'the last thing' on his mind despite helping Inter qualify for next season's UEFA Europa League.
"I’ve never been a coach who sought out contracts," he said.
"I worked. And then when the time comes to start a new season you have to do it beyond what the contract might involve.
"Everything has to be clear in a club in order to be able to start strongly. Every coach that wants to transmit his philosophy has to be enthusiastic about it.
"A contract is the last thing on my mind, and beyond that I’m only interested in talking with the club now. We'll have several meetings and talk, and then we’ll all be relaxed and happy to start the new season."
Victor Obinna's second-half brace led Chievo to the win over Inter, who had nothing to play for with fifth place secured.
Mazzarri said he learned very little from the encounter, and he will have discussions with the club regarding transfers.
"Do we need more players for next season? I’ll discuss that with the club. There’s no sense in doing it now," he said.
"I always try to take stock of things with my staff, and that also goes for games that don’t have any bearing on the standings.
"There are always many things you can observe. It was a peculiar season with a lot of things to manage and many peculiar situations. You can’t gather too much information from a game like this."
