There were reports that the Rossoneri had accepted the French side's bid for the 27-year-old defender, but the two clubs are still discussing a fee
It had been claimed on Monday evening that the two sides had agreed a fee for the Brazil international but the 67-year-old insists that nothing has been decided as of yet.
"The deal is not done," Galliani, who arrived in Paris on Tuesday told Ansa. "It will take a long time to find a solution."
As Goal.com revealed, the Ligue 1 outfit have offered €42 million for Thiago Silva but that fee could rise by €8m because of numerous performance-related bonuses.
However, Milan are seeking a guaranteed €50m from the transfer of their most prized asset and Galliani is said to have made that clear during his talks with PSG sporting director Leonardo at the club's headquarters on Tuesday.
The negotiations are now set to drag into the second day, with Sky Sport Italia claiming that Galliani has cancelled his scheduled fight back to Milan.
Meanwhile, France Football is reporting that Thiago Silva is currently awaiting the outcome of the talks in a Parisian hotel with his representatives.
The 27-year-old centre-back, who arrived at San Siro in 2009 from Fluminense, has reportedly been offered a deal worth €1m per month.