City were presented with the Premier League trophy after Sunday’s 0-0 draw with Huddersfield at Etihad Stadium.
“Here, it is more difficult,” said the Spaniard. “In England, it’s special because it’s so tough.”
He told BBC Radio 5 live that was the case due to the “huge contenders and the quality”.
Guardiola, 47, won La Liga six times while playing for Barcelona, then led them to the title in his first year as manager – 2008-09.
Two more followed in successive seasons before he moved to Bayern Munich, who won three consecutive Bundesliga titles under his management.
His first season as City manager ended with the team 15 points adrift of champions Chelsea in the Premier League.
But they have swept aside their challengers this season, winning the league – for the first time since 2013-14 – with five matches to spare.
“We are delighted with what we have done and the way we have done it,” Guardiola told BBC Radio 5 live.
“At the start of the season, you never know what is going to happen. You just have to prepare the team well and the title was the consequence.
“We’ve seen in recent seasons how the team who won the Premier League has not even qualified for the Champions League the following year so making back-to-back titles in this league will be tough but we accept the challenge.”