The Serbian star told a press conference prior to his opening match at the French Open that he planned to compete in next month’s Olympics.

Djokovic is an 18-time Grand Slam champion but would be seeking a maiden Olympic gold medal in Tokyo.

He won bronze on his Olympic debut at Beijing 2008.

Djokovic lost to eventual champion Andy Murray in the semi-finals at London 2012, before losing to Argentina’s Juan Martin Del Potro in the bronze-medal match.

Del Potro also overcame Djokovic in the first round at Rio 2016, where the Serbian made a tearful exit.

With the attendance of spectators set to be decided this month, amid the COVID-19 pandemic, Djokovic said the support of fans would be key when making his final decision on whether to compete.

"If there's not going to be any crowd, then I'll consider if I want to go or not," Djokovic told a press conference.

"As I heard, there's going to be some crowd, local crowd from Japan only.

"As I understand, 20 to 30 per cent of the capacity.

"Right now I am planning to go, and I'm very excited about that."

Japanese reports have suggested domestic spectators could only be permitted to attend events if they provide either proof of vaccination or a negative COVID-19 test, it has been claimed.

Overseas fans have been banned from attending the Games amid the COVID-19 pandemic, but organisers have held off on a decision on domestic fans to date.

A decision is likely to be made towards the end of June, with state-of-emergency measures in 10 areas including Tokyo set to expire on June 20.

Roger Federer, the 20-time Grand Slam champion, also admitted to having doubts over competing at Tokyo 2020.

Federer is yet to win an Olympic gold in the men's singles contest, despite competing at Sydney 2000, Athens 2004, Beijing 2008 and London 2012.

He finished as runner-up to Murray at London 2012 and clinched men's doubles gold at Beijing 2008 alongside Stan Wawrinka.

Federer then missed Rio 2016 through injury.

"I don’t know, I feel two ways," Federer said, according to Sky Sports.

"I would love to play.

"I wish things were better around the world that we wouldn’t even have to debate the thought of is it going to happen, am I going to play or not.

"My wish and hope and dream is that I can play it.

"But it needs to make sense for me, my team, my family, my country.

"I’m still waiting to see how things are going to develop the next couple of weeks and month."

Federer, who will turn 40 in August, is expected to compete in the mixed doubles with Belinda Bencic.