It seems Princess Beatrice will be breaking the rules of the royal book when tying the knot with Edoardo Mapelli Mozzi, as the duo are reportedly planning a low-key affair instead of traditional and lavish royal wedding.

According to a friend, the pair are looking for a low-key venue instead of Windsor Castle to host the wedding, and even a marquee in "Prince Andrew and Sarah Ferguson's back garden" will do the work. Reception at Windsor Castle is also not on the cards.

The would-be bride will be violating the age-old royal diktat that 'one should never marry at a castle that is not one's own'. She may forgo a carriage ride and procession as well. The daughter of Prince Andrew, Duke of York and Sarah has also told her parents about her wish for a low-key wedding, reports Daily Mail.

Buckingham Palace announced Princess Beatrice's engagement to property tycoon Edoardo Mapelli Mozzi towards the end of September. The date of the nuptials has not been announced yet.

The 31-year-old princess is being able to opt-out of royal protocol as she has dropped to ninth-in-line since the birth of Prince Harry and Meghan Markle's son, Archie in May. Due to this, she did not even have to ask Queen Elizabeth for approval to marry her fiance, and is not obliged to endure the lavish procession.

There also won't be a pressure to have the occasion broadcasted, which was there in the case of her elder sister Princess Eugenie, coverage of whose wedding was turned down by the BBC.

Princess Eugenie married Jack Brooksbank at St George's Chapel last October, and the royal affair was also criticised for costing the taxpayer about two million pounds to police.

One of the reasons behind Beatrice's choice for a low-key affair is said to be the situation with fiance Mozzi's ex-girlfriend Dara Haung, with whom he shares two-year-old son, Wolfie. There is speculation that the 31-year-old royal might invite Haung to the wedding since their son Wolfie has been named the groom's best man.

Haung had also cleared the air around the situation and said, "I wish the best for Edo and Beatrice and look forward to uniting our families."

Princess Beatrice
Princess Beatrice at Prince William and Kate Middleton's wedding in 2011 Getty

The couple earlier reportedly wanted to be married in Italy, but the plan was cancelled since the queen "won't fly to Europe".

Royal spokesperson Ingrid Seward told OK Magazine that the princess' grandmother and the 93-year-old monarch will not fly to Europe for the wedding. "I think in her heart Beatrice would like to be married in Italy where Edo's from, but there's no way the Queen will fly to Europe for the wedding so it will have to be in England," Ingrid said.