Prince Harry has once again torpedoed reconciliation efforts and fuelled speculation about the King’s health.

Prince Harry has once again proven his critics – especially those in royal circles – right. In an exclusive interview with The Guardian, the King’s youngest son has said he has no regrets when it comes to the very public, scathing attacks he has made on the Royal Family.

Instead of offering an apology or holding his hands up that he may have crossed a line, Harry said: “My conscience is clear.” This is the same Harry who is desperate for reconciliation and a meaningful relationship with his father, the King.

After five years of hurling abuse at his family and torpedoing any meaningful relationship with his older brother by attacking both him and his wife, the Princess of Wales, by portraying her as cold and unfeeling towards Meghan Markle, Harry still won’t admit that his decision to pen a tell-all biography, sit down for a scathing interview with Oprah Winfrey and film a bombshell documentary series with his wife about their royal exit was a mistake.

How can Harry treat the King, who relented and met with his son for tea despite significant unease from the Queen and the Prince of Wales, like this? He didn’t need to stoke the flames and continue down his woe-is-me past.

Harry could have deflected the question, or offered a hint of an apology without needing to say “I’m sorry, I regret the hurt I’ve caused my family”. But instead, he’s doubled down on his bullish approach and shown once and for all that he cannot be trusted.

Asked if he regretted writing his book or making the Netflix films, Harry replied: “I know that [speaking out] annoys some people and it goes against the narrative. The book? It was a series of corrections to stories already out there. One point of view had been put out, and it needed to be corrected.”

He added: “I don’t believe that I aired my dirty laundry in public. It was a difficult message, but I did it in the best way possible. My conscience is clear.”

Harry’s comments about his lack of regrets are one thing, but to allude to the King’s health just months after his eyebrow-raising remark that he didn’t know “how much longer” his father had left to live is unforgivable.

Harry said that over the coming year, “the focus really has to be on my dad”, and has set alarm bells ringing once more. It’s an incredibly unhelpful comment and risks fuelling more speculation about the King’s prognosis, as he continued to undergo weekly cancer treatment.

I just can’t believe that Harry would repay his father’s generosity by meeting with him last week with such inflammatory, hurtful comments. The only person he’s serving are those who knew such a meeting would end like this, such as the Queen, the Prince of Wales and his top team of advisers.

The Duke of Sussex had just started to win back public favour after his four-day charm offensive in Britain and his visit to Ukraine, but not even a week later, he has blown it. Prince William is right, Harry cannot be trusted and should not be welcomed back.