The Brazilian’s contract is set to expire at the end of the season, but Chelsea are willing to offer a two-year deal as opposed to his favoured three– a situation which could see him leave West London.
Willian was widely linked with a move away from England, having been courted by Barcelona for more than two years.
The 31-year-old joined Chelsea in August 2013 following a short stint with Russian club Anzhi Makhachkala.
"It’s a difficult situation because Chelsea offered me two years and they are not going to change what they offered. I said I wanted three more years," the former Shakhtar Donetsk man told Esporte Interativo.
"The situation is difficult because of this. I really don’t know if it will be possible [to stay].”
“My goal is to continue working and focus on the remainder of the season, so that Chelsea can continue winning games.”
"I have a clear head and focused for the rest of the season that we have left.”
“I think it’s difficult [to stay]. Let’s see what happens.”
As an ever-present member since his debut, Willian has won five trophies with the London-based club which includes two Premier League titles and one Europa League.