Haaland's hat-trick made it 94 goals in 96 starts for City in just over two seasons.
Guardiola beamed: “He did it in Salzburg. He did it in Germany. The numbers are ridiculous,” the manager told media at his post-Ipswich press conference.
“He can compete in terms of goals with Ronaldo and Messi.
“The numbers are incredible for his age. He’s an incredible threat for us and we’re really happy to have him.
“Hopefully he can be here for many years. That would be really good for us.
“You know how important he is. The numbers, scoring goals is unbelievable.”
The manager continued: “I said a few weeks ago he feels better than previous seasons.
“He struggled to handle it, maybe not too much holidays. I remember at the beginning he said I’m tired, I’m a little drained.
“This season with no Euros and relaxed, he arrived really well.
“When there is something wrong, always there is something coming that is positive. “When you have a defeat, take the positive and move forward.
“He would have loved to have gone to Euros with Norway. It was not the case.
“Okay, relax, play good this season and try to help Norway qualify for the next tournament.”