The first official portrait of Princess Charlotte has been released.

The charming photo, taken by the Duchess of Cambridge, shows the Princess being held tenderly by her older brother Prince George.

The message from Kensington Palace accompanying the image reads: "We're delighted to share the first photo of Prince George with his little sister Princess Charlotte. The photo of Prince George and Princess Charlotte was taken by The Duchess of Cambridge in mid-May."

The picture is one of a set of four, which was taken around two weeks ago at Anmer Hall, the royal couple's ten-bedroom country home in Norfolk.

The other pictures show Prince George looking adoringly at his baby sister and planting a kiss on her forehead.

Kate's father, Michael Middleton, took the first official picture of George, which was released when he was less than a month old, in August 2013.

In a break from royal protocol, Kensington Palace 'exclusively' released the single photograph on their Twitter and Instagram accounts as a thank you to social media users at 9pm tonight.

Kensington Palace also posted a picture of the thousands of letters and gifts sent by well-wishers following the royal birth on 2 May.

It said: "The Duke & Duchess are very grateful for the wonderful messages they've received on the birth of Princess Charlotte. Thank you to everyone who took the time to make handmade gifts for Princess Charlotte - here are a few of them!"

The Princess was born on the morning of 2 May, in the Lindo wing of St Mary's hospital, Where Prince George was also born. She arrived at 8.34am, weighing 8lb 3oz. An official announcement about the birth came just after 11.15am after the couple had informed their respective families.

By 6pm, the royal couple emerged from St Mary's Hospital in London to a cheering crowd and the world's media, as the Princess made her first public appearance.

The Princess will be christened on 5 July, Kensington Palace announced on Friday (5 June).The service will take place at St Mary Magdalene Church at the Queen's Sandringham Estate in Norfolk where Prince William and Kate Middleton live. The christening will be carried out by Archbishop of Canterbury Justin Welby.

She is fourth-in-line to the British throne after her grandfather, Prince Charles, her father Prince William and brother Prince George, who is almost two years old.