Prince William and Catherine, Duchess of Cambridge, are reportedly applying for planning permission to build a two-storey basement under the orangery in Kensington Palace.
Duchess Catherine and Prince William
The 34-year-old royal and his wife Catherine - with whom he shares two children Prince George, three, and Princess Charlotte, 22 months - are set to move back into the Palace after William steps down from his role as an Air Ambulance pilot this summer.
Officials from Historic Royal Palaces have applied to build the two-storey basement in order to free up the palace suits that are currently in use, in order to make room for the couple's staff.
A planning permission application submitted to Kensington and Chelsea council and obtained by the Daily Telegraph newspaper states: "The addition of a basement storey is required to allow for the accommodation of administration which must necessarily be moved out of rooms leased from the Royal Household in Kensington Palace."
Whilst Prince William and Duchess Catherine have used Princess Margaret's former apartment 1A in Kensington Palace as their official residence since 2014, they have spent most of their family time at their country home in Anmer Hall, Norfolk.
Now, the famous family will "increasingly base their family" at their official residence in the palace.
A statement released previously by the Palace said: "Since 2014 The Duke and Duchess of Cambridge have used Apartment 1A at Kensington Palace as their official residence when carrying out Royal duties, while basing their family primarily at their home in Norfolk.
"This arrangement has allowed The Duke to work as a pilot with the East Anglia Air Ambulance, a role he has valued hugely.
"Their Royal Highnesses love their time in Norfolk and it will continue to be their home.
"From this Autumn, however, The Duke and Duchess will increasingly base their family at Kensington Palace.
"As they have in recent years, Their Royal Highnesses are keen to increase their official work on behalf of The Queen and for charities and causes they support, which will require greater time spent in London.
"Prince George will begin school in September and Princess Charlotte will also go to nursery and eventually school in London as well.
"His Royal Highness will finish his role with the EAAA in the summer in line with his commitment to fly with them for two years."
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