Prince William and Prince Charles 'will always have issues' in their 'difficult' relationship, claims a royal expert.

Both men are set to become King and have seen their royal duties expand following the Queen's recent health scare.

Speaking to Newsweek, royal author Penny Junor explained how "competition" between the two, who have a "very similar job", may become a problem as their royal roles continue to grow.

She said: "I think it's always going to be a little bit difficult.

"They are two people doing a very similar job.

"With all fathers and sons I think there's an element of competition, the older man not really wanting to step over just yet and let the younger take his crown.

Prince William and Charles 'will always have issues' in their relationship, says expert
William and Charles have seen their roles expand following the Queen's health issues

"I think that's always going to be a slight issue."

Penny did caveat her concerns by saying that the pair seem closer than ever, and that they are pulling in the same direction.

Over the past few years, both have been ramping up their work in support of Her Majesty, undertaking more of the duties typical of the sovereign, reports the Express.

These include investitures, a duty also carried out by Princess Anne, and travelling abroad on behalf of the Crown or the UK Government.

Prince William and Charles 'will always have issues' in their relationship, says expert
The pair have been collaborating over the Duchy of Cornwall, which William will take on when Charles becomes King

Since the beginning of the pandemic, the monarch has only completed special one-on-one investitures, including the knighting of late Captain Tom Moore in July 2020.

The Queen stopped undertaking long-haul flights in 2015, when she visited Malta with Prince Philip one last time.

Moreover, the father and son have increased their collaboration on the Duchy of Cornwall, which will be administered by the Duke of Cambridge once Charles becomes King.

William now attends regular meetings focused on the Duchy with the latest taking place this week on November 23, according to the Court Circular.

Prince William and Charles 'will always have issues' in their relationship, says expert
Penny described how there will always be "competition" between the father and son

In 2019, the Duke of Cambridge demonstrated an understanding of the importance of the Duchy for his family and a true commitment during the two-part ITV documentary Prince Charles: Inside the Duchy of Cornwall.

Speaking to a tenant, Mervyn Keeling, about the Duchy, William said: "I think it's important, Mervyn, about the family angle. I really do.

"I've started to think about how I will inherit the Duchy one day and what I do."

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