Former world number one Andy Murray has revealed that he is contemplating surgery to rectify a long-standing hip problem after being forced to withdraw from another tournament.

Murray, now down to 16th in the men's singles rankings following six months away from the sport, was due to take part in the Brisbane International this week.

The 30-year-old announced on Monday morning that he is unable to compete Down Under, though, and he has yet to decide whether to participate in the Australian Open - the first Grand Slam of the year - midway through this month.

Alongside an image of himself in his school days, Murray posted the following statement on his Instagram account: "Firstly I want to apologise to @brisbanetennis for withdrawing at late notice and to everyone who wanted to come along to watch me play (or lose). The organisers couldn't have been more understanding and supportive and I'll always remember that. Thank you.

"I've obviously been going through a really difficult period with my hip for a long time and have sought council from a number of hip specialists. Having been recommended to treat my hip conservatively since the US Open I have done everything asked of me from a rehab perspective and worked extremely hard to try get back on the court competing.

"Having played practice sets here in Brisbane with some top players unfortunately this hasn't worked yet to get me to the level I would like so I have to reassess my options. Obviously continuing rehab is one option and giving my hip more time to recover. Surgery is also an option but the chances of a successful outcome are not as I high as I would like which has made this my secondary option and my hope has been to avoid that. However this is something I may have to consider but let's hope not.

"I choose this pic as the little kid inside me just wants to play tennis and Compete.. I genuinely miss it so much and i would give anything to be back out there. I didn't realise until these last few months just how much I love this game. Everytime I wake up from sleeping or napping i hope that it's better and it's quite demoralising when you get on the court it's not at the level you need it to be to compete at this level.

"In the short term I'm going to be staying in Australia for the next couple of days to see if my hip settles down a bit and will decide by the weekend whether to stay out here or fly home to assess what I do next. Sorry for the long post but I wanted to keep everyone in the loop and get this off my chest as it's really hurting inside. Hope to see you back on the court soon."

Murray, who was due to face Ryan Harrison in the last 16 of the Brisbane international on Thursday, last competed competitively at Wimbledon in July.