Team Diana back Harry at Invictus anniversary as her brother Earl Spencer and her sister Lady Jane Fellowes lead guests in support of the Duke's project

Princess Diana's siblings were quick to show their support for Prince Harry yesterday during the Invictus Games anniversary service, while the royal family kept their distance - despite only being a few miles away.

The late Princess of Wales' younger brother Earl Spencer and elder sister Lady Jane Fellowes walked in side-by-side to St Paul's before chatting to their now US-based nephew. 

The Duke of Sussex had cut a lonely figure as he climbed the steps of the cathedral - unaccompanied by his wife Meghan Markle, who remained in California with their two children.

Meanwhile King Charles, who was invited to attend the service in central London, held the first garden party of the season at Buckingham Palace.

The monarch was joined by Queen Camilla, the Duke and Duchess of Edinburgh, the Princess Royal and the Duke and Duchess of Gloucester for the first of the summer festivities.

The only senior royals missing were the Prince and Princess of Wales. William was handing out awards in Windsor, while Kate is still undergoing treatment for cancer. 

Prince Harry's spokesperson had claimed on Tuesday the King had been too busy to see his youngest son during his fleeting visit to the UK. 

Last night, however, Palace sources suggested no formal requests for a meeting had been made. 

Despite well-documented tensions with the Windsors, Prince Harry has remained close to his mother's family over the years - particularly Lady Jane.

Lady Jane, the middle of the three sisters, four years older than Diana, has long been seen as a confidante and a steadying influence in his life. 

She was asked to give a reading during Harry's wedding to Meghan in 2018 and was one of the first members to be invited to meet their infant son Archie - even before Prince William. 

Throughout his bombshell memoir Spare, he gave a 'stand out thanks' to Lady Jane, her elder sister Lady Sarah McCorquodale and Earl Spencer but failed to mention the late Queen, King Charles or his brother.

It is therefore little surprise that two of the siblings turned out at yesterday's ceremony to give support to Diana's youngest child.

As well as his aunt and uncle, Harry was surrounded by a number of dignitaries, politicians and close friends.

His lawyer David Sherbourne was in attendance while former army officer Mark Dyer - who helped mentor Harry particularly after his mother's death - was also in the congregation. 

Rishi Sunak's wife Akshata Murty also joined the group, dressed in a military-style green coat with gold buttons, where she was joined by Minister of State for Veterans' Affairs Johnny Mercer.

Other stars within the crowd included former Olympic champion triple jumper Jonathan Edwards.

Huge crowds had gathered outside St Paul's to catch a glimpse of the estranged royals rare appearance on British soil, with some shouting 'we love you Harry' as he walked out of his car.

The Duke was warmly greeted by the Dean of St Paul's, the Very Reverend Andrew Tremlett, before being escorted to his seat under the cathedral's great dome.

Whilst inside the cathedral he spoke to the clergy, as well as Earl Spencer before taking his seat. 

The Duke of Sussex, who remains estranged from many family members after a string of attacks on the Royal Family in recent years, said on Tuesday that he had been told his father did not have time to see him this week while he is staying in the UK.

Charles had not been able to find time to see his son Prince Harry this afternoon as he attends the first Buckingham Palace garden party of the summer season.

The King had a busy day yesterday with meetings planned in the morning ahead of the garden party. He then attended his weekly audience with the Prime Minister in the evening followed by a Privy Council meeting.  

The Duke of Sussex has flown into London for the Invictus engagements and there were hopes that he would see the King. But a spokesman for Harry said  that the monarch's 'full programme' meant the get-together would not happen.

Yet royal insiders last night told the Telegraph that no formal requests for a meeting with the King had been made.  

During the ceremony Harry took a seat next to his mentor Mark Dyer and exchanged a few words with his uncle Earl Spencer. 

The service began with the hymn Praise My Soul The King Of Heaven as a few miles away the King hosted the first Buckingham Palace garden party of the year.

The Dean of St Paul's told the congregation: 'We gather this evening to offer grateful thanksgiving to Almighty God for the work of the Invictus Games Foundation, and in this their 10th anniversary year, we celebrate the tremendous achievements of the numerous competitors across 23 nations.

'We give thanks for the inspiring vision and compassion that formed the foundation and, chiefly, for the resultant decade of profound and transformational work.

'We lament the pain, cost and indignity of war and terror, and pray for a world where justice shall reign and where the nations will find their longed for unity.

'We recall, with admiration, the skill and determination of those who seek to repair, rehabilitate, and reclaim the lives of those living with serious illness or injury: changing and saving lives.'

He gave a reading from 1 Corinthians 12 4-11. Actor Damian Lewis, 53, meanwhile read out the Invictus poem with the service being conducted by William Ernest Henley. 

An emotional reading was also given by Michelle Turner who is the UK Invictus Games Team vice-captain. She read a personal poem about how the games had helped her recovery and impacted her family. 

At the end of the reading she tearfully said: 'Thank you Invictus, for giving me my life back.' 

As he left the cathedral on a balmy evening in the capital, the Californian-based royal greeted large crowds.

He was heard asking two fans from New York what had brought them to the UK. When they responded they were here for a wedding, the Prince jokingly asked it was 'in there?' referring to St Paul's Cathedral.

The Duke joked around with one enthusiastic royal fan who had her arms outstretched with two phones to try and get the best shot of Harry. 

'Why have you got 2 phones?' he laughed, 'it doesn't make sense!' 

Hundreds of people had joined the crowd that was tightly guarded by police officers.

Shouts of 'we love you Harry' could be heard as the Prince did his walkabout, while others screamed with excitement until Harry got into a Land Rover and drove off.

It is not known where Harry is staying while in Britain as he now has no official home after being asked to leave Frogmore Cottage.

He is expected to stay in the UK until tomorrow before flying to Nigeria where he will meet up with Meghan for a quasi-royal tour that is also expected to highlight the Invictus Games.

Harry spent Tuesday in the capital attending a summit that reflected on the 10th anniversary of the Invictus Games, which stages sporting events for wounded, sick or injured veterans or serving military to aid their recovery.

He told delegates at the event, held at the Honourable Artillery Company's headquarters on the edge of the City of London: 'Sometimes you... look back and go 'Look at what we've done'.

'But also given the state of the world, there is so much more to do and I think a lot of uncertainty - but what we've created is a global community.'

Harry is also not expected to see his estranged brother Prince William who held an investiture ceremony at Windsor Castle yesterday.

William continues to balance work with looking after his three children while his wife Kate undergoes preventative chemotherapy for cancer and recovers from serious abdominal surgery in January.

Today William will fly to Cornwall for further official engagements – and the King will meet staff and families of the 3 Royal School of Military Engineering in Surrey.

Then on Monday there will be a rare joint visit for Charles and William, as the King officially hands over the role of Colonel-in-Chief of the Army Air Corps to William at the Army Aviation Centre in Middle Wallop, where Harry previously learnt to fly.

Harry has travelled to the UK to commemorate the Invictus Games milestone with those who have been involved with the paralympic-style tournament and mark the decade-long support competitors have received. 

Charles and Harry last met soon after the King announced his cancer diagnosis in February and his son rushed from America to see his father.

That was the first time Harry had seen his father in person for 17 months, and they had a half-hour meeting before Charles left London to recuperate at Sandringham following treatment.

But this time, a spokesman for Harry said: 'In response to the many inquiries and continued speculation on whether or not the duke will meet with his father while in the UK this week, it unfortunately will not be possible due to His Majesty's full programme.

'The duke of course is understanding of his father's diary of commitments and various other priorities and hopes to see him soon.'

Just hours after Harry's statement, palace officials announced a new joint engagement for Charles and William.

It is one of dozens of official engagements being planned for the 75-year-old monarch in the coming months after his doctors gave him the all-clear to undertake more public work once again while continuing his cancer treatment.

On Monday, Charles met the prime minister of the Republic of Fiji at Buckingham Palace, before retiring to Clarence House – three miles away from Harry's event.

Harry now lives with his wife Meghan Markle and children Archie, who turned five on Monday, and Lilibet in a £12million mansion in Montecito, California.