Journalist Sandro Barbosa wrote on Twitter that the 29-year-old was considering a proposal from the Brazilian club.
Willian quickly refuted the claims, responding to Barbosa directly.
He wrote on Twitter: "Hello Sandro, all right? Sorry, but I'm not negotiating with Palmeiras and my agent has received no contact from the club.
"I have no plans to return to Brazil right now. A hug!"
He also responded to another claim that he wanted to return to his homeland in January.
He said: "Hi Juca, all right? Sorry, but I don't have the goal of returning to Brazil and never spoke, nor my representative, with no one. This is nothing but speculation. A big hug!"
The Selecao star has had his playing time diminish considerably under Antonio Conte, and with the World Cup coming up next year, speculation has linked him with a move away from the club to ensure he makes Brazil's squad for Russia.