King Charles IIIis showing his appreciation for emergency service workers ahead ofQueen Elizabeth’s funeral on Monday — and his son,Prince William, made a surprise appearance to join him.

On Saturday, the 73-year-old monarch and his 40-year-old heir met with police officers and staff at the Metropolitan Police Service Special Operations Room in London to thank them for their work ahead of the Queen’sstate funeral.

King Charles and Prince William.Hollie Adams/Getty

LONDON, ENGLAND - SEPTEMBER 17: King Charles III and Prince William, Prince of Wales arrive to meet emergency service workers at Lambeth HQ on September 17, 2022 in London, England. His Majesty The King thanks Emergency Service workers for their work and support ahead of the funeral of Queen Elizabeth II. The Queen died at Balmoral Castle in Scotland on September 8, 2022, and is succeeded by her eldest son, King Charles III. (Photo by Hollie Adams/Getty Images)

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The pair also met with officers from other forces and officials from key partners including the London Ambulance Service and London Fire Brigade, Transport for London and the Army.

King Charles.Hollie Adams/Getty

LONDON, UNITED KINGDOM - SEPTEMBER 17: Britain’s King Charles III greets Interim Deputy Commissioner of the Metropolitan police Dame Lynne Owens, Mayor of London Sadiq Khan, Home Secretary Suella Braverman, (obscured) Met Police Commissioner Sir Mark Rowley and Lord-Lieutenant of Greater London Sir Kenneth Olisa as he arrives to meet emergency service workers at Lambeth HQ on September 17, 2022 in London, England. His Majesty The King will thank Emergency Service workers for their work and support ahead of the funeral of Queen Elizabeth II. The Queen died at Balmoral Castle in Scotland on September 8, 2022, and is succeeded by her eldest son, King Charles III. (Photo by Hollie Adams/Getty Images)

Prince William.Vianney Le Caer/Shutterstock

Mandatory Credit: Photo by Vianney Le Caer/Shutterstock (13396139r) Prince William meets with emergency service workers in Lambeth to thank them ahead of Queen Elizabeth funerals King Charles III thanks emergency workers at Lambeth HQ, London, UK - 17 Sep 2022 His Majesty The King will thank Emergency Service workers for their work and support ahead of the funeral of Queen Elizabeth II at the Metropolitan Police Service Special Operations Room (SOR).

Queen Elizabeth’s state funeral will take place at Westminster Abbey in London on Monday, gathering about 2,000 world leaders and royals from around the globe.

ISABEL INFANTES/AFP via Getty

Britain’s Prince William, Prince of Wales talks with members of the public waiting in the queue to pay their respects to Queen Elizabeth II, Lying-in-State at the Palace of Westminster, in London on September 17, 2022. - Queen Elizabeth II will lie in state in Westminster Hall inside the Palace of Westminster, until 0530 GMT on September 19, a few hours before her funeral, with huge queues expected to file past her coffin to pay their respects. (Photo by ISABEL INFANTES / AFP) (Photo by ISABEL INFANTES/AFP via Getty Images)

On Friday, King Charles and his wifeQueen Camillacompleted their tour visiting the four countries of the U.K. following the death of the Queen with a visit to Wales. The country is of particular significance to Charles, who spent most of his life as the Prince of Wales.

The royal couple also attended engagements in Scotland on Monday, including the Queen’s four childrenfollowing her coffin in a processionthrough Edinburgh and laterstanding vigilinside St. Giles' Cathedral.

They alsogreeted well-wishersgathered outside of Hillsborough Castle in Belfast, Ireland on Tuesday.

King Charles.Aaron Chown/PA Images via Getty

King Charles III meets members of the public in the queue along the South Bank, near to Lambeth Bridge, London, as they wait to view Queen Elizabeth II lying in state ahead of her funeral on Monday. Picture date: Saturday September 17, 2022. (Photo by Aaron Chown/PA Images via Getty Images)

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On Wednesday, the coffin of the late monarchtraveledfromBuckingham Palaceto Westminster Hall in a solemn procession. The procession included her four children — King Charles,Princess Anne,Prince AndrewandPrince Edward— and several of her grandchildren, includingPrince William,Prince Harryand Peter Phillips.

source: people.com