Prince Philip is portrayed as an adulterer in the new series of 'The Crown'.

Prince Philip

Prince Philip

The 96-year-old royal - who recently celebrated his wedding anniversary with Queen Elizabeth - features as a sex-mad character who cheats on the Queen multiple times in the new series.

But the show's creator, Peter Morgan, has stressed that the programme is simply developed with entertainment in mind.

Speaking to The Sun newspaper, Peter said: "What I have to do is write a story about people at the centre of British life who are human beings.

"If you're hoping that tries to pick holes in the royal marriage, I wouldn't dream of it. Their marriage is a triumph by any standards."

On the show, the Queen is portrayed by actress Claire Foy, while Matt Smith stars as Prince Philip.

Meanwhile, Queen Elizabeth recently became the oldest reigning head of state, after Zimbabwe president Robert Mugabe, 93, ended his three-decade reign by stepping down from the role.

As a result, the Queen is now the oldest head of state alive today, though she is closely followed by 90-year-old Beji Caid Essebsi, who is the president of Tunisia.

Back in 2015, she also surpassed her great-great-grandmother, Queen Victoria, as the longest-reigning monarch, having now ruled over Great Britain for a whopping 65 years.

What's more, her 70-year marriage to Prince Philip is the longest in royal history.

To commemorate the landmark, a new portrait of the pair was recently issued, which sees the couple framed on either side by portraits painted in 1781 of George III and Queen Charlotte, who were married for 57 years - which was the longest royal marriage until their own.