The Queen finally meets great-grandaughter Lilibet at Windsor Castle

LONDON, ENGLAND - JUNE 02:  (L-R) Queen Elizabeth II, Prince Louis of Cambridge, Catherine, Duchess of Cambridge and Princess Charlotte of Cambridge watch the RAF flypast from the balcony of Buckingham Palace during the Trooping the Colour parade on June 02, 2022 in London, England. The Platinum Jubilee of Elizabeth II is being celebrated from June 2 to June 5, 2022, in the UK and Commonwealth to mark the 70th anniversary of the accession of Queen Elizabeth II on 6 February 1952.  (Photo by Chris Jackson/Getty Images)
The Queen appeared on the Buckingham Palace balcony with three of her grandchildren on Thursday, before meeting grandaughter Lilibet for the first time soon after at a private lunch (Getty)

Prince Harry and his wife Meghan Markle have introduced the Queen to her great-grandaughter Lilibet for the first time, at a private lunch at Windsor Castle.

The pair joined senior members of the Royal Family for the lunch on Thursday, with son Archie and daughter Lilibet, who turns one on Saturday.

They are staying at their UK home of Frogmore Cottage, in the grounds of the castle, while visiting Harry's grandmother as part of the four-day Platinum Jubilee celebrations.

The lunch took place behind closed doors following the Trooping the Colour at Buckingham Palace, at which only senior working royals appeared on the balcony with the Queen.

Harry and Meghan instead watched the ceremony from the Major General’s Office overlooking the Horse Guards Parade.

Prince Harry and Meghan Markle, Duke and Duchess of Sussex arrive for a service of thanksgiving for the reign of Queen Elizabeth II at St Paul's Cathedral in London, Friday, June 3, 2022 on the second of four days of celebrations to mark the Platinum Jubilee. The events over a long holiday weekend in the U.K. are meant to celebrate the monarch's 70 years of service. (AP Photo/Matt Dunham, Pool)
The Duke and Duchess of Sussex are in the UK to join Prince Harry's grandmother, the Queen, celebrating her Platinum Jubilee (PA)

The couple have been said to be keeping a low profile to avoid overshadowing Harry's grandmother during the celebratory weekend. They will hold a birthday party for Lilibet on Saturday, but pictures are not expected to be released to the public.

The Duke and Duchess of Sussex, who relinquished royal duties and moved to America two years ago, were not allowed to stand with other members of the family on the Buckingham Palace balcony on Thursday as they are no longer serving royals.

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However, they were due to join a host of Royals at a national service of thanksgiving on Friday at St Paul's Cathedral.

It was announced late on Thursday that “with great reluctance” the Queen could not attend the service.

Buckingham Palace said in a statement that the monarch had experienced “some discomfort” during Thursday’s celebrations.

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The news came on Thursday evening, soon after it was announced that her son Prince Andrew would not attend the event, having contracted COVID-19.

It is not known if he was at the private lunch at the castle.

Andrew stepped down from public life after the furore over his friendship with paedophile billionaire Jeffrey Epstein, and paid millions to settle a civil sexual assault case to Virginia Giuffre, who he claimed never to have met.

The duke no longer uses his HRH style, although he has denied the claims made against him.

Watch: Royals put feuds aside to celebrate Queen's jubilee