A collection of behind-the-scene photos from the royal wedding of have sold for over $12,000 (over N2 million) at auction.

The photos were taken from the reception held at Buckingham Palace on 29 July 1981, where the royal couple were joined by guests including the Queen, Princess Anne, Princess Margaret and Prince Andrew.

The auction was carried out by a Boston-based company who obtained the exclusive photos from the collection of an assistant to photographer Lord Patrick Lichfield.

READ: Original clip of Princess Diana and Prince Charles' royal wedding released online [VIDEO]

Lichfield was the only photographer allowed to take informal photographs of the royal family and their guests at the Palace following their wedding ceremony at St. Paul's Cathedral.

"The candid and unrehearsed moments of the fairytale wedding captured in these photographs show a seldom seen side of the Royal family," said Bobby Livingston, Executive VP at RR Auction.

READ: Princess Diana's bridesmaid says she "deeply regrets" selling her dress [PHOTOS]

"It's not surprising that photographs commanded such an impressive figure— the public adored Princess Diana and these never-before-seen photos have an incredible amount of sentimental value for the millions of fans that remember the people's princess."

The released photos also showed Diana in her famous wedding dress being arranged in the Throne Room for official photographs, were left out of the late Princess' and Prince Charles' wedding album.