Sir Keir Starmer and his wife Lady Victoria Starmer have arrived at Aberdeen airport en route to stay with King Charles and Queen Camilla at Balmoral.

The Sunday Express revealed last week that Sir Keir had accepted an invitation to join His Majesty on the Scottish estate.

It is tradition for the serving Prime Minister and his or her partner to be invited to join the monarch at Balmoral towards the end of the summer months just before Parliament is back in session. The House returns on September 2 this year.

“The prime minister and his wife received their invitation earlier this month and they accepted,” said the source.

According to the source, the Prime Minister and his wife will be offered accommodation in the main castle while Their Majesties will reside in their private cottage on the estate, Birkhall.

Rishi Sunak and his wife Akshata Murty paid a visit to the Scottish castle last year, and were seen arriving at Crathie Kirk with King Charles and Queen Camilla.

Sir Keir Starmer and the monarch have known one another for exactly a decade. They first met when the then-Prince Charles knighted the Prime Minister back in 2014.

The premier was granted the honour for his work as Director of Public Prosecutions. Starmer was made a Knight Commander of the Order of the Bath during an Investiture ceremony at Buckingham Palace.

King Charles, Queen Camilla and most of the Royal Family are already on the Balmoral estate for their annual summer holiday, allowing for the occasional public engagement at the same time.

Prince William, Princess Kate and their three children – Prince George, 11, Princess Charlotte, 9, and Prince Louis, 6 – have joined the monarch along with Princess Anne and her husband Timothy Laurence.

Mike and Zara Tindall have joined with their family for some of the time.

The Duke and Duchess of Edinburgh and their children, as well as Prince Andrew and Sarah Ferguson are also in attendance. The Duke and Duchess of Sussex have not been invited.