Tennis superstar Novak Djokovic on Wednesday admitted meeting a journalist when he knew he had Covid-19, describing it as an "error of judgement".

Djokovic also conceded he submitted a false declaration to the Australian government about his travel history between flying to Melbourne, though he blamed it on his agent.

The comments were in a statement posted to Instagram aimed at addressing the controversies surrounding his efforts to play at the Australian Open while being unvaccinated.

Despite the admissions, Djokovic insisted other reports about him appearing in public following his positive test for Covid-19 as "misinformation".

He said the reports of his public appearances after his claimed infection were "very hurtful" to his family.

The 34-year-old world number one entered Australia last week with a vaccine exemption due to a positive test for Covid-19 on December 16.

The following day, however, he appeared without a mask at the launch of a Serbian stamp bearing his image and at an event in Belgrade for young tennis players.

Djokovic said he only received the positive results of the PCR test for Covid-19 infection on December 17, after the youth tennis event. 

He made no mention of the stamp ceremony.

The player said he had a negative rapid antigen test on December 16 and then had the PCR test out of an "abundance of caution".

The following day, he took a second rapid antigen test, which was also negative, before going to the children's tennis event.

"I was asymptomatic and felt good, and I had not received the notification of a positive PCR test until after that event," he said.

But Djokovic admitted that he also went ahead with an interview and photoshoot with French sports newspaper L'Equipe on December 18.

"I felt obliged to go ahead and conduct the L'Equipe interview as I didn't want to let the journalist down, but did ensure I socially distanced and wore a mask except when my photograph was being taken," he said.

"On reflection, this was an error of judgement and I accept that I should have rescheduled this commitment."

Australian media have also focused heavily on the accuracy of Djokovic's travel declaration, reportedly filled out before he flew in from Spain.

A copy of his declaration showed a tick in the box to confirm he had not and would not travel in the 14 days before landing in Australia on January 5.

But the player had reportedly been in Serbia before Spain. 

"On the issue of my travel declaration, this was submitted by my support team on my behalf," Djokovic said on Instagram.

"My agent sincerely apologises for the administrative mistake in ticking the incorrect box about my previous travel before coming to Australia.

"This was a human error and certainly not deliberate."