High-level talks are under way to gradually bring King Charles and Prince Harry together in a public show of unity for the first time in at least six years.

In the strongest indication yet that the Duke of Sussex is making positive steps towards a reconciliation with senior royals, it is understood that courtiers in both households are tentatively discussing how to get father and son together more frequently over the next year, with a view to them finally appearing jointly at a public event.

The last time Harry and his father appeared on their own and happy together at an official engagement was in April 2019 at the 'Our Planet' global premiere in the Natural History Museum in London.

Since Harry stepped down from royal duties in 2020, they have only been pictured with other family members at the state funerals of Prince Philip and Queen Elizabeth.

The extraordinary development comes after Harry spent 50 minutes with King Charles at Clarence House earlier this month, their first face-to-face meeting in 18 months as the monarch continues to be treated for cancer.

An appearance together of the King and Harry would be interpreted as thawing of their relationship and the acceptance of the Duke – and Meghan and their children Archie, six, and Lilibet, four – back into the royal fold after several years of bitter recrimination between Harry and his family.

The move comes as relations allegedly sour between the King and the Prince of Wales amid claims Charles is 'unhappy' that William's workload is less than his own. In turn, his heir is said to be angry about the meeting with Harry.

Sources say that as part of the cautious plans being drawn up to resolve the crisis:

• Harry agreed to keep a low profile during Donald Trump's visit as a goodwill gesture to his father.

• The Duke might take part in more UK public events, though not officially as a working member of the Royal Family.

• Harry is said to be 'hopeful' of re-establishing a relationship with William despite the froideur between them since Megxit.

Despite the cautious positive steps, Harry is said to be 'realistic' that some reputational damage from the last few years is irreversible.

But after last week, many royal commentators agreed that Harry was back in his element, meeting the public and larking around for the cameras with children.

The warm public reaction to him did not go unnoticed at the Palace, sources insist, where working members of the Royal Family – particularly those keen to do the bread-and-butter public engagements – are in short supply.

A source said: 'Harry's visit to the UK was not about trying to show up or compete with his brother – in fact, the opposite.

'It was to remind William that Harry can be there to take some of the load off, given some of the criticism William has received for carrying out a lower number of engagements than his father.

'That doesn't need to be as part of the "working" Royal Family. It can just be doing what he loves to do and does best – supporting causes close to them both, such as the Diana Award and conservation.

'More than anything, though, he wants to see his father more. He wants to make him proud and be there to support him through his treatment.' 

On his later trip to Kyiv, when asked about meeting the King, all Harry would say was that in the coming year 'the focus really has to be on my dad'.

As part of rebuilding trust between the pair, Harry agreed, at the King's request, to avoid any publicity which would distract from President Trump's visit.

The Sussex royal household were given two days off to coincide with the trip and Harry ensured he did not carry out any engagements at home or abroad, and was not photographed at his home in Montecito, California.

In a BBC interview this year Harry said he knew that some members of his family will 'never forgive him' for the accusations he made alongside Meghan in their TV chat with Oprah in 2021, and in his excoriating memoir Spare.

For the moment William remains firmly in that camp. Last week, a source said relations between the brothers are now so bruised that William can't even stand the mention of Harry's name.

But Harry, who plans to come to the UK 'four or five times' a year from now on, is said to be hopeful that he can at least find a working relationship with William. 

'Whatever he can do to continue rebuilding those relationships and that trust, he will do,' a source said.

Royal biographer Tina Brown suggested that the King, who made 372 appearances last year, was 'less irritated' by Harry than he was by William.

She said that tensions are brewing between the King and heir over William's workload, which pales in comparison to his cancer-stricken father and has been punctuated by numerous holidays.

Ms Brown added the King feels William's carefully cultivated image as a doting father, while genuine, is a tacit criticism of his past shortcomings as a parent.

She said Harry's return to the UK had been a great success for him, which is 'bad news for the Prince of Wales'.

'The King is, I am told, less irritated with the prodigal Harry than he is with his elder son and heir. 

'Somehow, William's parenting dedication always seems couched as a tacit criticism of the King's own paternal deficiencies.'

If the King does play a significant role in rehabilitating Harry, it will not be the first time he has done this for someone close.

He faced an uphill battle to have Camilla accepted publicly and worked closely with his mother on a message she issued during her Platinum Jubilee celebrations.

Royal sources now believe the same could happen for Harry.

Last night Buckingham Palace and a spokesman for the Duke of Sussex declined to comment.

King, 76, meets Ethel, 116, his oldest living fan 

The King took a trip down memory lane as he met Ethel Caterham to mark her 116th birthday – a milestone making her the world's oldest person.

Charles, 76, visited Mrs Caterham at her care home in Lightwater, Surrey, where the pensioner, who has lived through the reigns of six British monarchs, chatted to him about his younger days. She told him: 'I remember when your mother crowned you [Prince of Wales]... and all the girls were in love with you.'

Mrs Caterham had also said he was 'handsome', to which the King joked: 'Well, all that's left of him anyway.'