The Spaniard, whose new contract expires in 2021, had one year left to run on his previous deal which he signed upon arrival from Bayern Munich in June 2016.
"I'm so happy and excited".
Manager Guardiola said now was not the time for looking ahead to see if they could improve on their league performance next term.
'I enjoy working with our players every day and we will try to do our best together in the coming years. "I like a lot how they play".
Starting out in top-flight management in 2008, Guardiola spent four years overhauling Barcelona - winning three Spanish league titles and the Champions League twice among 13 honors.
Sequels are hard but 'Deadpool 2' gets it mostly right
With Deadpool 2 opening in theaters this week, Fox has one more promo for the superhero sequel up its sleeve. However, none of these things are game-breaking and can be easily ignored while watching the film.
Karnataka: BS Yeddyurappa's oath and other 10 key developments
BJP, Central government and their governors have been exposed in front of the nation, says Congress leader Ghulam Nabi Azad. The Supreme Court dismissed the plea by JD (S) and Congress to stay the formation of the government.
Mohamed Salah's boots to go on display at British Museum
With a Champions League Final and a World Cup campaign looming on the horizon, we're willing to be Salah's 2018 is going to get even better.
That says something about how relatively unimportant a win at Wembley is, given there wouldn't be much debate if United had the offer of the Premier League title on the table instead.
Second, but some way off Manchester City in the season just gone, Manchester United will once again be closest challengers for the Premier League title. In doing so he has embodied the passion and commitment we all have for the Club.
They ended the season with the most points, most goals, most wins, best goal difference and biggest points-winning margin of any title-winning side, along with a host of other records.
Pep Guardiola has revealed the only business Manchester City are planning for the summer transfer window is to find a midfield replacement for Yaya Toure and perhaps buy another forward.
Executive Vice Chairman Ed Woodward said talk of the creation of a 24-team Club World Cup tournament illustrated the importance of the game to broadcasters.
Guardiola joined Man City at the start of the 16-17 season, and went trophy-less for the very first time in his career, calling the season a "failure". "Having Pep committed to Manchester City for the next three seasons gives us the stability to be able to continue to improve and bring more success to the club".