Journalist Simon Cambers added that Murray "is back hitting but not ready to compete yet," and the 32-year-old three-time Grand Slam champion "plans to build fitness in January."
The Australian Open confirmed Murray will miss the tournament, which begins January 20 at Melbourne Park:
Murray had announced plans to retire through tears at a press conference days before the 2019 Australian Open, the reason then a painful, lingering hip injury:
"I spoke to my team and I told them I can't keep doing this and that I need to have an end point, because I was just playing with no idea when the pain was going to stop. I said, look, I think I can kind of get through this until Wimbledon. That is where I would like to stop. I'm also not certain I'm able to do that.
"I can still play to a level, not a level that I'm happy playing at. But it's not just that. The pain is too much, really. It's not something I want. I don't want to continue playing that way. I've tried pretty much everything that I could to get it right, and that hasn't worked."
However, Murray released a statement including his plans "to return to the tour" in June (h/t NBC Sports). The Scotland native went 11-7 in 2019 with his only title coming at the European Open in October.
Murray was looking forward to returning to Australia and playing again where he previously had thought his career was drawing to a close, he said in a statement released Saturday:
"I've worked so hard to get myself into a situation where I can play at the top level and I'm gutted I'm not going to be able to play in Australia in January. After the AO this year, when I wasn't sure whether I'd be able to play again, I was excited about coming back to Australia and giving my best, and that makes this even more disappointing for me.
"Unfortunately I've had a setback recently and as a precaution, need to work through that before I get back on court competing."
Murray last won a Grand Slam when he claimed Wimbledon in 2016.