The `I Look to You` singer was forced to cancel a concert in Paris after being diagnosed with an upper respiratory infection, and has now been forced to postpone two shows in England on Thursday (08.04.10) and Friday (09.04.10) and in Scotland on Saturday (10.04.10).
Whitney was taken to hospital 06.04.10 with nose and throat problems and advised against performing by doctors.
A source told Sky news the singer is suffering from `chronic rhinopharyngitis`, a swelling of the mucus membranes in the nose and pharynx, and an infection, the cause of which has not been identified.
A spokesperson for her record label RCA said: "With great disappointment, WhitneyHouston has postponed her first three concerts in the UK due to illness.
"Doctors visited Whitney late last night in Paris and confirmed that she was suffering from an upper respiratory infection. Upon medical advice Whitney has been advised that she cannot perform to allow her time to recover."
The `Nothing But Love` World Tour 2010 concerts, in Manchester on Thursday and Friday have been rescheduled to June 16 and 17 and the Glasgow concert will now take place on May 1.
Tickets for all shows will remain valid, and the tour is still planned to continue next week, taking in UK cities Birmingham, Nottingham, Dublin, Newcastle and London.