Kate Middleton, the Duchess of Cambridge, delivered a baby boy on late night Monday at St Mary's Hospital here.

"Her Royal Highness The Duchess of Cambridge was safely delivered of a son at 4.24pm (local time). The baby weighs 8lbs 6oz," the Kensington Palace said in a statement.

The baby was born in the private Lindo Wing of the hospital in central London.

Prince William was with his 31-year-old wife when she delivered their child at the hospital in Paddington, where his mother, Princess Diana, gave birth to him in June 1982.

The cost of a suite at the unit is GBP 6,265 for a one-night stay with no complications and GBP 2,200 for each extra night.

All rooms have satellite TV, wi-fi, radio and a safe. The wing also offers a "comprehensive wine list".

Fresh bouquets of flowers are delivered every day and blackout curtains ensure total privacy.

Gynaecologists, paediatricians, midwives, nurses, breast -feeding consultants and nursery nurses are all on hand.