Madonna has postponed the dates of her world tour after developing a serious bacterial infection that left her in intensive care.

The 64-year-old singer was due to kick off the North America leg of her 'The Celebration' world tour, on July 15 in Vancouver, Canada.

The tour is to mark the 40th anniversary of her musical career and would also include two shows at Madison Square Garden in New York in August.

She was later scheduled to travel to London for four sold-out shows at the O2 Arena from October 14 to begin the European leg of the tour, Sky News reported.

Later on in the year, she was also booked for two more dates at the O2 Arena in December.

Madonna needs to 'pause all commitments'

The US pop icon's manager, Guy Oseary, said in a statement: "On Saturday, June 24, Madonna developed a serious bacterial infection which lead to a several-day stay in the ICU.

"Her health is improving, however, she is still under medical care. A full recovery is expected.

"At this time we will need to pause all commitments, which includes the tour."

He added that a new start date for the tour and details for rescheduled shows would be shared in due course.

Just one week ago, Madonna shared a series of images with her 18.9m Instagram followers which appeared to show her in rehearsals, in a post captioned "The Calm Before The Storm".

Can you get a refund for Madonna's 'The Celebration' tour?

At the moment no details have been released concerning the possibility of a refund to people who may not be able to make a rearranged date on the tour.

As the tour is postponed rather than cancelled ticket holders will just have to wait and see when the new dates are locked in for.

In his statement, Mr Oseary did not mention any provisions for ticket refunds.