The Spaniard was in charge at Barcelona and Bayern Munich before replacing Manuel Pellegrini at City last summer.
“I will be at Manchester for the next three seasons, maybe more,” Guardiola, 45, told NBC prior to his team’s 2-1 win over Burnley on Monday.
“I will not be on the bench until I am 60 or 65 years old. I feel the process of my goodbye has already started.”
Guardiola, who gave an awkward post-match interview to BBC Sport – which you can watch at the top of this page, won 14 trophies in four years at Barcelona, including three La Liga titles and two Champions Leagues.
He took a year’s break before joining Bayern in 2013, leading the German team to three successive league titles but missing out on the Champions League.
Guardiola added: “I am arriving at the end of my coaching career, of this I am sure.”
City were reduced to 10 men against Burnley when Fernandinho was sent off after 32 minutes, but goals from Gael Clichy and Sergio Aguero gave them the lead.
Ben Mee pulled one back for the Clarets and, despite City holding on, Guardiola cut an edgy figure following the victory.
Asked at his post-match news conference about his comments to NBC, he said City “might be one of my last teams”.
Guardiola’s tetchy BBC interview
After City’s win over the Clarets, Guardiola was interviewed by BBC Sport’s Damian Johnson. Here is the tense exchange in full:
Johnson: “What was your view of the red card for Fernandinho?”
Guardiola: “You are the journalist. Not me.”
DJ: “You’re the manager. I’m sure the fans would like to know.”
PG: “Ask the referee – not me.”
DJ: “Are you concerned that’s his third red card this season? Is there a discipline problem with him?”
PG: “We will accept. Like I said before, the team with more ball possession we have always sending-off. I have to understand the rules here in England. I know you are specialist but I have to understand it.”
DJ: “So the interpretation is perhaps different in England?”
PG: “Of course, yes. Around the world our keeper in the box is fouled, not here. I have to understand that. Claudio Bravo is fouled.”
DJ: “It’s his fault?”
PG: “He is fouled. Here not – that’s OK but I have to understand that.”
DJ: “You don’t seem that happy that you’ve won.”
PG: “More than you would believe. More than you would believe, I am happy.”
DJ: “You’re not showing it.”
PG: “I’m so happy, believe me. I’m so happy. Happy new year.”
DJ: “Are Manchester City in the title race?”
PG: “Yesterday, no. Why today are we in the title race?”
DJ: “Thanks Pep.”
PG: “My pleasure.”