Dame Helen Mirren said she is "proud to be an Elizabethan" as she paid tribute to the Queen following her death at the age of 96.
The actress, 77, played the role of her majesty both on the silver screen and on stage and called her the "epitome of nobility" in her heartfelt post.
Her words, which she shared with her 1 million Instagram followers, were a fitting tribute and read: "I am proud to be an Elizabethan. We mourn a woman, who, with or without the crown, was the epitome of nobility."
Many of the Oscar-winning star's followers took to the comments section to share their own messages of condolence. Among them, one user wrote: "Sending love and strength to the Royal Family and all that sought inspiration from her life and actions. May she rest in peace! She was a really great and big one! A great person. This is a day I thought would never happen."
Another penned: "I’m so sad. 40 years ago, she was the only woman in power. I looked up to her with all of my heart as a little girl. God save the Queen."
The Queen's death was confirmed in a statement on Thursday which said she passed away peacefully at Balmoral Castle. The news followed reports all Her Majesty's children had rushed to be by her side after doctors became "concerned" for her health.
Following the news, famous faces across the world paid their respects to Britain's longest-reigning monarch.
Among those was Sir Mick Jagger, who reflected on how the Queen had "always been there" throughout his life. The Rolling Stones star shared an image of the Queen on his Instagram alongside the caption: "For my whole life Her Majesty, Queen Elizabeth II has always been there.
"'In my childhood I can recall watching her wedding highlights on TV. I remember her as a beautiful young lady, to the much-beloved grandmother of the nation. My deepest sympathies are with the royal family."
Princess Diana's butler Paul Burrell also shared an emotional tribute on TalkTV in which he called Her Majesty his "surrogate mother".
He said: "I am devastated to know the Queen is no longer there. For me she was my surrogate mother in many ways, she was incredibly warm."
Britain has now entered days of national mourning with long-held plans, which have already begun to be put into action being known as Operation London Bridge and Operation Unicorn.
Today (September 9) will mark 'D-Day' as defined within the schedule, with the coming days to be referred to as D-Day plus the number of days that have passed since her death.
