City have been linked with a big-money move for Borussia Dortmund striker Erling Haaland but Guardiola believes that the club will only spend astronomical sums on players if they feel they will improve the team significantly.
He said: "So far the club have decided not to spend close to £100m or more than £100m for a player.
"Maybe in the future, it's going to happen when the club decides it's necessary to improve the team for the next five or 10 years.
"But so far the club, the organisation, the CEO, the sporting director, have decided not to do it and that's why they haven't done it. Maybe in the future, I don't know."
City will get a closer look at Haaland as they face Dortmund in the Champions League quarter-finals but Guardiola has played down speculation linking the club to the Norwegian striker.
Asked about Haaland's possible value, he said: "I don't know. It is a question for Borussia Dortmund and his agent.
"I understand people ask about Haaland, he is an exceptional striker, but it is not appropriate for me to talk about him."
City are looking to win a historic quadruple of trophies but Guardiola feels that their sensational form in the Premier League is irrelevant on the continental stage.
He said: "Why should we win the other competitions just because we are leading the Premier League?
"The only concern is to try to win the game. Win this game and after comes Leeds, and after we go to Dortmund to win that game.
"If we play good and deserve it we go through. If not, we will try next season."