The former Germany international says that the Blues' triumph at the Allianz Arena in 2012 proved that financial muscle dictates who wins what in the modern game
The Premier League outfit claimed the most prestigious prize in club football in 2012, after nine years of being bankrolled by Roman Abramovich, one of the richest men in the world.
Kahn believes that Chelsea's success underlines the importance of monetary power in the modern game, though did not exclude his former club when listing sides who have benefited from their financial might.
"It is the deciding factor," the former Germany international told Kicker.
"For promotion to the Bundesliga, you now need a budget of €20 million to €25m (£16.5m-£20m). To win the Champions League, €300m (£250m).
"Abramovich bought the title but what makes make [Chelsea] any different to Manchester City, Real Madrid, Barcelona or Bayern?"
Uefa introduced Financial Fair Play Regulations in 2011 in the hope of curbing the spending of Europe's top clubs, with the aim of creating a more even playing field.