The Duke of Edinburgh is expected to remain in hospital for “observation and rest” into next week, sources have said. Prince Philip was admitted to King Edward VII’s hospital on Tuesday evening after feeling unwell and walked unaided into the medical centre. The duke, who will celebrate his 100th birthday on 10 June, was a non-emergency admission for an undisclosed reason. It is not coronavirus related. Sources told PA: “Following consultation with his doctor, the Duke of Edinburgh is likely to remain in hospital for observation and rest over the weekend and into next week. As we have said previously the doctor is acting with an abundance of caution. The duke remains in good spirits.” Philip has spent the lockdown with the Queen at Windsor Castle, where the royal couple have spent much of the past 12 months of the pandemic. In January they had their Covid-19 vaccines. On Thursday the Queen carried out her first official in-person event of the year when she made one of her most senior royal aides a Knight Commander of the Royal Victorian Order during a ceremony at the castle. The duke was last admitted to hospital in December last year, for four nights, on the advice of his doctor as a precautionary measure due to a “pre-existing condition”. He was discharged on Christmas Eve. He retired from public duties in 2017 and was last seen in public in July 2020 when he transferred his role of colonel-in-chief of The Rifles in a ceremony in Windsor to the Duchess of Cornwall, Camilla. News of the duke’s extended stay in hospital comes as the palace announced that the Duke and Duchess of Sussex, Harry and Meghan, will not return as working royals and will give up their royal patronages. While Harry and Meghan will retain their HRH titles, they will not use them, sources said. They will remain the Duke and Duchess of Sussex, titles the Queen bestowed on to them.