PSG are believed to have had an offer of 65 million euros (£51 million) accepted for the stars, who are widely accepted to be two of Serie A's finest players.
An agreement with Brazil defender Silva over personal terms has reportedly already been found as PSG pursued the defender in June, before he signed a new contract with Milan that could be broken almost immediately. He is set to earn 7.5m euros per year for five years at Parc des Princes.
Talks with Sweden striker Ibrahimovic have been more problematic, though PSG hope to secure him to a three-year contract with 12m euros per season.
Leonardo has travelled to Sweden to meet the striker, who boasts spells with Barcelona, Inter, Juventus and Ajax on his CV, and will now hold further talks with his agent, Mino Raiola, in an effort to close one of the most remarkable deals in the recent history of European football.
"Yes, we are negotiating and we also spoke yesterday in Sweden," Leonardo told Sky Sport Italia.
"We will soon meet with Raiola and then we will see what can happen.
"At the moment everything is possible, because the transfer market is like that - it's always open. The deals can only be considered done, when they are in fact done."