The Brazilian stunned Inter by recently leaving as coach after just six months having also quit as AC Milan manager last year following a one-season stint.
With Inter and Milan bosses saying the 41-year-old feels he is more suited to a director role than working as a coach on the training ground, Leonardo declared he had come to his former club PSG to "build a long-term project."
"Paris is the only European capital not to have a competitive team. But the potential is there," he told reporters in impeccable French before backing coach Antoine Kombouare, who led the side to fourth place in Ligue 1 last term.
"I will call him this evening. I do not want to change [the squad's] routine... I coached a team a month ago, I know what it's like," the Brazilian added.
The recent arrival at PSG of wealthy buyers from Qatar has fuelled rumours of huge transfer bids despite the French league struggling to compete with its European peers in recent years but Leonardo tried to calm the speculation.
"We are not talking about buying 13 Messis. We are in no hurry to recruit," he said, adding that his contract for the all-powerful role within the sporting division of the club is "indefinite".
Leonardo, who finished his playing career at AC Milan in 2003, spent one season at PSG in 1996/97.
