In a statement posted on Djokovic's Instagram account, he said he attended a children's tennis event the day after being tested for Covid-19.
"I had not received the notification of a positive PCR test result until after that event," the statement said.
"The next day, on 18 December I was at my tennis centre in Belgrade to fulfil a long-standing commitment for a L'Equipe interview and photoshoot. I cancelled all other events except for the L'Equipe interview.
"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.
"While I went home after the interview to isolate for the required period, on reflection, this was an error of judgement and I accept that I should have rescheduled this commitment."
Djokovic's statement also addressed the widely reported discrepancy in his travel declaration, published by the Federal Circuit and Family Court of Australia earlier this week. He attributed it to "human error" on behalf of his agent.
"On the issue of my travel declaration, this was submitted by my support team on my behalf - as I told immigration officials on my arrival - and 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. We are living in challenging times in a global pandemic and sometimes these mistakes can occur."
Australian immigration minister Alex Hawke has said a decision will not be made on Wednesday over whether to cancel Djokovic's visa.
The minister has since Monday been considering personally intervening in the matter after Djokovic won his court battle against the Australian Border Force.
Djokovic is the Australian Open defending champion and top seed.
He has won nine times in Melbourne and would make history if he is able to compete and goes on to make it 10 as it would take him to 21 Grand Slam victories, moving him ahead of rivals Rafael Nadal and Roger Federer.
The Australian Open draw is due to be held on Thursday.