The award-winning indigenous Australian musician - born Geoffrey Gurrumul Yunupingu - will be unable to play in Europe as planned this July.
[Gurrumul and guest at the 2011 ARIA Awards in Sydney]
A statement on the musician's website read: "Due to ongoing health issues Gurrumul has had to cancel his July European tour. He is currently in the care of his immediate family."
No further information has been provided at this stage.
Gurrumul was honoured with the 'Best World Music Album' accolade at last year's ARIA awards for his second studio album Rrakala.
He also won two prizes at last year's Deadly Awards, which celebrate achievement in indigenous communities.
Gurrumul was one of the contributing vocalists on Gary Barlow and Andrew Lloyd Webber's track 'Sing', which was commissioned for Queen Elizabeth II's Diamond Jubilee.
Watch a clip of Gurrumul performing in London below: