Queen Elizabeth II's cause of death was described as "old age" in the register of deaths released on Thursday.

The registrar general for Scotland, Paul Lowe, confirmed that the Queen's death was registered in Aberdeenshire on September 16th.

The document states that the 96-year-old monarch died at 3.10pm on 8 September at Balmoral Castle, Ballater. Princess Anne registered her mother's death.

Douglas James Allan Glass is noted as the certifying registered medical practitioner. Old age was the only cause of death listed. Glass was an apothecary to the Queen, her doctor in Scotland.

The record shows that the Queen died only three hours before Buckingham Palace made the announcement at 6.30pm.

The prime minister, Liz Truss, was told of the Queen's death at 4.30pm, Downing Street has previously said.

Old age is acceptable if the doctor certifying death has cared for the patient for a long time, was not aware of any disease or injury that contributed to death and had observed a gradual decline in the person's general health.

The Queen had been experiencing sporadic mobility problems during the final period of her life. She used a walking stick regularly in public after she was admitted to a private London hospital for preliminary investigations in October last year.

The monarch was soon back at her Windsor Castle desk, but spent the following three months under doctors' orders to only conduct light duties.

Following tradition, the Queen was spending her summer break at Balmoral, and a few days before she died performed one of her major duties of state and asked Truss to form a government and become her 15th prime minister.