Prince Harry is set to meet with King Charles for the first time in 20 months – though his brother William has reportedly rejected the invitation ‘out of hand’.

Reconciliation is ‘within reach’ between the Duke of Sussex and his father following an informal peace summit involving Buckingham Palace officials.

Harry is expected in London on September 8 for the third anniversary of Queen Elizabeth II‘s death where he will also attend the WellChild Awards – a charity event he has avidly supported.

A US source told The Mirror there was now a ‘determination on both sides to make this happen’.

The source added: ‘Nobody is pretending the wider family issues have been resolved, but this is about beginning with Charles and Harry.

‘For the first time in a long time, there’s a genuine sense that reconciliation is within reach.

‘Prince Harry’s team and the Palace have opened a line of communication, and there is every hope that father and son will see one another when the Duke returns to London in September.’

The source said there was a ‘feeling the time is right’ following 20 months apart and as the King continues his cancer treatment.

Pictured: Prince Harry and Meghan Markle at a Thanksgiving Service at St Paul’s Cathedral

The monarch and his youngest son, Prince Harry, are pictured together in December 2018

Harry and William are pictured attending the unveiling of a statue of their mother, Princess Diana at The Sunken Garden in Kensington Palace, London on July 1, 2021

It is expected the encounter will be a ‘simple face-to-face conversation between a father and a son’ rather than a ‘grand gesture or set-piece meeting’.

‘Privacy and dignity’ have also been highlighted as priorities.

However, a reconciliation between the prince and his brother is said to have been ‘rejected out of hand’.

In the midst of the planned meeting, it is understood Harry’s wife Meghan Markle will remain in California with the couple’s two children, Archie and Lilibet.

The last time the King saw his grandchildren was June 2022 when Harry and Meghan returned for the late Queen’s Platinum Jubilee celebrations.

The Duke of Sussex’s trip on September 8 will mark his first visit since he failed to appeal the downgrading of his security protection in the UK.

Last month Harry and Meghan’s new chief of communications, Meredith Maines, met with Tobyn Andreae, the King’s communications secretary, at the Royal Over-Seas League (ROSL) a three-minute walk from Clarence House, the monarch’s London residence.

It was not known whether it had been Charles or Harry who extended the olive branch, but insiders said the summit was the strongest sign yet of the determination on both sides to resolve the bitter House of Windsor feud.

King Charles and Prince Harry’s senior aides held a secret peace summit in London (pictured: the head of communications for Royal Family Tobyn Andreae (left) and Meredith Maines head of communications for The Sussexes (right) with Liam Maguire, who runs the Sussexes’ PR team in the UK (centre)

In May Harry had said he ‘would love a reconciliation’ as he did not know ‘how much longer my father has’.

Though, the public appeal was still followed by little personal contact.

Despite September’s anticipated meeting, relations between Harry and the Prince of Wales are thought to remain frosty.

A separate source told the Mirror Prince William felt his brother had ‘repeatedly chosen public exposure over private resolution’ and expressed a determination not to be ‘dragged into the headlines every time there’s a new contract to promote’.

There was said to be an ‘issue of trust’ and perceived inability for Harry and Meghan to ‘keep things private’.

In 2020 when Harry and Meghan stepped down as working royals, hopes were high within the firm that a halfway point could be found.

The Duke and Duchess of Sussex claimed their decision to ‘step back as “senior” members’ was to become more financially independent and to enjoy more privacy from the prying eyes of the media.

Prince Harry and Meghan, Duchess of Sussex, during their interview with Oprah Winfrey in March 2021

But what followed was a slew of allegations against the monarchy. In their March 2021 interview with Oprah Winfrey the pair claimed the had suffered racism and that Meghan had even been left suicidal.

In 2022 they went on to accuse the palace of ‘unconscious bias’ before Harry’s memoir Spare in early 2023 made a number of new claims.

King Charles is said to have been ‘deeply saddened’ by the allegations but has left the door open to reconciliation.

The Duke and Duchess of Sussex and Buckingham Palace have been contacted for comment.