Bryan Adams. Picture: AP

Canadian star Bryan Adams responded to a question about his rumoured romance with the later Princess Diana during an interview on 'Watch What Happens Live with Andy Cohen'.

The 58-year-old singer is believed to have been romantically linked to the Diana during the 1990s, following the collapse of her marriage to Prince Charles, but during an interview on 'Watch What Happens Live with Andy Cohen', the 'Run to You' hitmaker remained coy about the speculation.

The host said to him: "There are many rumours that you and Princess Diana were once romantically involved.

"Her butler said that he used to sneak you into Kensington Palace. How would you characterise your relationship with Princess Diana?"

The '(Everything I Do) I Do It for You' hitmaker replied, cheekily: "Great friends. And she didn't sneak me in, I would just roll up."

Andy subsequently asked whether they were "friends with benefits", and Bryan answered: "She was just ... we were good friends."

The 'Heaven' singer shared some X-rated details about his personal life, revealing that the one and only time he took a picture of his penis was when he had the image framed and sent to Sir Elton John.

Bryan also revealed the chart-topping Brit - who is married to David Furnish - was happy to have received such an unusual gift.

He shared: "When I gave it to him he said, 'I'm going to change that frame'. Now it's in gold. I think it's on his mantelpiece."