Queen Elizabeth II on Saturday said she wanted Camilla, the wife of her heir Prince Charles, to ultimately be known as Queen Consort, in a major statement on the eve of the 70th anniversary of her accession to the throne.

The 95-year-old British monarch said it was her "sincere wish" that when Charles becomes king, Camilla will be known as Queen Consort. It had been previously expected that Camilla, 74, would be known as Princess Consort when Charles, 73, accedes to the throne.

Addressing the nation in a written statement signed "Your Servant, Elizabeth R," the Queen said that when "in the fullness of time, my son Charles becomes King, I know you will give him and Camilla "the same support that you have given me".

"It is my sincere wish that, when that time comes, Camilla will be known as Queen Consort as she continues her own loyal service," she added.

The statement shows that the Queen is planning for the future after her death and holds Camilla, who married Charles in a civil ceremony in 2005, in high esteem.

The couple, now known as the Duke and Duchess of Cornwall, had a highly publicised relationship that ended their previous marriages and there had been doubts over whether the public would accept Camilla becoming known as queen.

But she has become a hard-working member of the royal family and has seen her public approval rating grow.

In December, the Queen appointed Camilla, a member of the ancient Order of the Garter, the only spouse of her children to be granted this honour.

Britain's Sunday newspapers swiftly put the story on their front pages.

"Camilla WILL become Queen," wrote the Daily Mail, while The Sunday Times wrote "Queen anoints Queen Camilla", saying the move ended "years of controversy and confusion over Camilla's future title".

A spokesperson for the couple said they were "touched and honoured".

Britain's Queen Elizabeth II (R) has said she wanted Camilla (C), the wife of her heir Prince Charles (L), to ultimately be known as Queen Consort
Britain's Queen Elizabeth II (R) has said she wanted Camilla (C), the wife of her heir Prince Charles (L), to ultimately be known as Queen Consort POOL via AFP / JACK HILL

The Queen issued a personal and significant message on the eve of the 70th anniversary of the day that her father, King George VI, died from lung cancer and she became monarch at 25.

As usual, the Queen is at her Sandringham estate for the anniversary.

She wrote in her message that: "It is a day that, even after 70 years, I still remember as much for the death of my father, King George VI, as for the start of my reign."

On Sunday, she will become the only British monarch ever to have reigned for 70 years.

"As we mark this anniversary, it gives me pleasure to renew to you the pledge I gave in 1947 that my life will always be devoted to your service," the Queen said, referring to a speech she gave on her 21st birthday.

The Queen said she looks ahead "with a sense of hope and optimism" as the nation is set for a summer of Platinum Jubilee celebrations including a four-day weekend in June.

"As I look forward to continuing to serve you with all my heart, I hope this Jubilee will bring together families and friends, neighbours and communities - after some difficult times for so many of us," she added.

She called for the nation to "enjoy the celebrations and to reflect on the positive developments in our day-to-day lives that have so happily coincided with my reign".

In her message, the Queen referred to her own 73-year marriage to Philip, who died last April at 99.

When she became Queen, he gave up a successful naval career to become her loyal consort.

"I was blessed that in Prince Philip I had a partner willing to carry out the role of consort and unselfishly make the sacrifices that go with it," she said.

The Queen marks a historic milestone in her reign as the royal family faces the hugely embarrassing possibility of her middle son Prince Andrew testifying in a US court in a civil sexual assault case.

She moved swiftly to remove Andrew from public life, while he has been staying at her royal residences.