Photos: Elizabeth II marks Platinum Jubilee with 'Queen Camilla' announcement

London: Queen Elizabeth II on Sunday became the first British monarch to reign for seven decades, expressing her "sincere wish" for Camilla, the wife of her heir Prince Charles, to ultimately be known as Queen Consort.

Elizabeth II made the announcement in a message renewing her pledge to spend her life serving the nation as she began her Platinum Jubilee in subdued fashion at Sandringham, her estate in eastern England.

In a message addressed to the public signed "Your servant, Elizabeth R", the Queen said late Saturday she wanted "to express my thanks to you all for your support". She said she wanted to renew a pledge she gave on her 21st birthday "that my life will always be devoted to your service".

Britain's longest-serving monarch acceded to the throne aged 25 on February 6, 1952, following the death of her father King George VI. With the main Platinum Jubilee celebrations set for this summer, the Queen said she hoped the events would "bring together families and friends, neighbours and communities".

'Historic reign': Stressing the Queen's ongoing role, Buckingham Palace released a photo taken at Sandringham this week showing her working on one of her famous red dispatch boxes used for government business.

With the main Platinum Jubilee celebrations set for June, Prime Minister Boris Johnson said he was looking forward to "when we will be able to come together as a country to celebrate her historic reign". He also praised the Queen's "inspirational sense of duty and unwavering dedication".

Queen Elizabeth II attends party on Jubilee eve: A smiling Queen Elizabeth kicked off celebrations for the 70th anniversary of her accession to the British throne by inviting local community groups on Saturday to her Sandringham residence in the east of England.

The queen's guests at Sandringham included Angela Wood, who as a cookery student in 1953 helped to create Coronation Chicken, a curry and mayonnaise-based dish invented to celebrate Elizabeth's reign and that is still enjoyed today.

The queen, wearing a light blue dress, also cut a celebratory cake baked by a local resident and heard a rendition of "Congratulations" played by a concert band, Buckingham Palace said.

On Saturday, the Queen held a reception for locals at Sandringham, reportedly her largest in-person public engagement since the autumn health scare.