Prince William could face a dilemma over funding Prince Archie and Princess Lilibet as well as Prince Harry and Meghan Markle if the Sussexes return to the Royal Family fold.
The Duke and Duchess of Sussex currently live in California with their two children.
However, there have been several reports that Meghan and Harry are coming under increasing financial pressure to fund their lifestyle as lucrative deals begin to dry up.
The couple's bumper deal with Netflix remains intact but they were recently dropped by Spotify.
Prince William could face a dilemma over funding Prince Archie and Princess Lilibet if Prince Harry and Meghan Markle return to the Royal Family fold.
Prince Harry is reported to have recently reached out to his brother Prince William in order to discuss the possibility of the Sussexes returning to the UK.
Prince William receives £24million a year from the Duchy of Cornwall and currently has a surplus which will diminish as he eventually funds Prince George, Princess Charlotte and Prince Louis.
However, the surplus may disappear if Prince Harry and Meghan Markle returned to the Royal Family fold.
Prince Willliam may have to fund the Duke and Duchess of Sussex duties, housing and the schooling of Archie and Lilibet as well as other costs that could put the heir to the throne's finances under pressure.
Royal commentator Richard Fitzwilliams told GB News that if Meghan and Harry did rejoin the monarchy as working members, they would be funded by the Duchy of Cornwall.
He said: "The answer would be the Duchy of Cornwall.
"There may not be a problem in funding them as they need young blood as there are few working royals under 70.
"However, the idea that after everything that has happened that Meghan and Harry could just walk back in is beyond extraordinary."
Prince Harry is reported to have recently reached out to his brother Prince William
Prince Harry previously claimed in his autobiography that prospect of funding him and Meghan was too much for his father King Charles.
The Duke of Sussex claimed that Charles had told him he was "already having to pay" a lot for William and Kate.
Harry wrote: "Pa didn’t financially support Willy and me, and our families, out of any largesse. That was his job. That was the whole deal."
He added regarding funding Meghan within the Royal Family: "Pa might have dreaded the rising cost of maintaining us, but what he really couldn’t stomach was someone new dominating the monarchy, grabbing the limelight, someone shiny and new coming in and overshadowing him."