Queen Elizabeth II may be forced to break royal protocol for Boris Johnson if he becomes new PM (Image: GETTY)
If Mr Johnson becomes the next prime minister on Wednesday he will likely be invited to visit the Queen at her Highlands estate in early September with his partner Carrie Symonds. However, according to royal protocol, unmarried couples who are guests of the Queen at any of her residences are not permitted to stay overnight. The royal protocol even applied to Prince Harry and Meghan Markle at Christmas in 2017 when they visited the Queen at Sandringham.
Instead, the engaged couple were forced to stay overnight at Anmer Hall, the nearby home of the Duke and Duchess of Cambridge.
A year later, the married couple were allowed to sleep overnight at Sandringham.
If Mr Johnson and Ms Symonds do not get married before September, the Queen may be forced to break royal protocol.
However, Mr Johnson and Ms Symonds could stay in a lodge on the estate - but this could be viewed as an unnecessary snub.
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