Australian pop princess Kylie Minogue has cancelled her upcoming world tour over fears for her health. The singer, 39, had planned a tour to mark her 40th birthday next year (08), but has cancelled on the advice of medics. Minogue brands the move "heartbreaking", but concedes it is "too soon" after her two-year long battle with breast cancer. She says, "The tour is not going to happen, it is far too soon. I can't do it next year. It kind of breaks my heart because that is what I'm in this business for. Not being able to go ahead with my plans is a real downer. "Every woman has to face up to new priorities, near the top is health. I take my health very seriously but not obsessively. Everything is about pacing yourself." Minogue pulled out of her Showgirl tour after being diagnosed with breast cancer in 2005 .