Novak Djokovic faces a dilemma if it becomes compulsory for players to get vaccinated before they can begin competing once the tennis season resumes following the hiatus created by the coronavirus pandemic, the world No. 1 said on Sunday.

"Personally I am opposed to vaccination and I wouldn't want to be forced by someone to take a vaccine in order to be able to travel," Djokovic said in a live Facebook chat with several fellow Serbian athletes.

"But if it becomes compulsory, what will happen? I will have to make a decision. I have my own thoughts about the matter and whether those thoughts will change at some point, I don't know. Hypothetically, if the season was to resume in July, August or September, though unlikely, I understand that a vaccine will become a requirement straight after we are out of strict quarantine and there is no vaccine yet."