Will and Kate's massive two-storey extension at Kensington Palace

Prince William and Kate Middleton are due to move to London full-time this year and plans are underway to renovate their Kensington Palace residence.

According to a repot in the Daily Mail, Historic Royal Palaces, the charity that takes care of the apartments in the grounds of the palace, has put in an application to build an extension next to the orangery.

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The massive 165ft-long extension, which is reported to be built underground, is said to be necessary to make room for the royal couple and their adorable two children, Prince George and Princess Charlotte.

Staff who are currently housed in the palace may be moved of their offices and into the three-storey building in the grounds of the palace.

The new building will also reportedly feature collection of dresses, which will be on display on the bottom level of the basement.

The red brick building behind the orangery is currently being used as a restaurant for visitors and it’s thought that will remain in place.

It comes after it was revealed that Wills and Kate are taking extreme measures to protect their privacy by erecting an extremely expensive hedge in their backyard.

The royal couple, who will live along the western side of Kensington Palace when they’re in London, planted an 820ft-long wall of conifers so their family can live in peace.

According to the Daily Mail, the hedge cost the taxpayer $33,000 (£20,000) but it will ensure three-year-old Prince George and one-year-old Princess Charlotte can enjoy a normal childhood away from prying eyes.

Privacy has always been very important for the royal couple, who have previously issued letters to those who come too close to their Anmer Hall residence in Norfolk.

A Kensington Palace spokeswoman said at the time: "The warm-hearted and understandable interest in the Royal Family and the Duke and Duchess of Cambridge needs to be balanced with their right to private family life - this is especially important for a family with very young children.

"This is a letter given by police to individuals found operating on or around the Sandringham estate, including Anmer, on behalf of the royal household.

“It reminds them of their responsibilities and the rights of the estate. Media are encouraged to speak to royal communications for further guidance about where they can operate on this private estate."

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