Royal insider Duncan Larcombe claimed Prince Harry and Meghan Markle need to make drastic changes if they want to have a relationship with the royals and save their marriage.

The author of "Prince Harry: The Inside Story" commented on the duke's recent return to London on July 1 for the unveiling of Princess Diana's statue. All eyes were on Harry and his brother, Prince William, and how they interacted with each other amid reports of their feud.

The public saw them smiling and laughing together, but others also noted that Prince Harry looked awkward with his "inappropriate" grin next to his somber-looking brother. Meanwhile, Larcombe claimed the Duke of Sussex's return to London for the statue unveiling could potentially make him question his priorities.

"Harry and Meghan seem to think they can co-exist in these two worlds – the world of British royals and American celebrity. Harry is loving the American life now – but he's still in the honeymoon phase," he told Closer magazine adding, "I think coming back and seeing his brother, especially against the very moving backdrop of a memorial for their mother, will maybe make him question what he's given it all up for."

Larcombe claimed that the memorial could leave Prince Harry torn between choosing Meghan Markle or his royal family. He pointed out that the duke has "totally sacrificed relations with his family for his new life with Meghan, and things seem to have been done her way and with her needs first."

However, there will come a point when he will ultimately "want and need his family" since they are "his flesh and blood" after all. The palace insider claimed that the Duke and Duchess of Sussex "will have to make compromises to make things work with the royals, and even to save their marriage." He warned that there "will be a point when he'll be torn between Meghan's world and his own family."

Larcombe suggested that Prince Harry and Meghan Markle "need to plan what they say and do moving forward and communicate with the royals." That is if they want to have a relationship with the duke's family.

Prince Harry and Meghan Markle
Prince Harry and Meghan Markle spoke out in an interview with Oprah Winfrey that immediately became one of the most extraordinary chapters in recent royal history Photo: AFP / OLIVIER DOULIERY