The Brazilian has been linked with a £16m move to Stamford Bidge this January and the 23-year-old has expressed his excitement at the possibility of playing in the Premier League.
Willian said: "Chelsea are known as one of the biggest and most successful clubs around.
"To play for them is a challenge I would accept and enjoy.
"If a deal doesn't go through, I'll understand. But I hope it happens."
The attacker has been capped twice by the Brazilian national side.