King Charles has said his late mother, Queen Elizabeth II, would have been troubled deeply by current affairs as he paid a heartfelt tribute to her on what would have been her 100th birthday. In a video message to honour the nation’s longest-reigning monarch, he said she had “remained constant, steadfast and wholly devoted to the people she served”.

The late queen would have turned 100 on Tuesday and the king said the day should be celebrated for a “life well-lived” rather than marking an “absence”, ahead of a series of royal events that will honour her. “Much about the times we now live in, I suspect, may have troubled her deeply, but I take heart from her belief that goodness will always prevail and that a brighter dawn is never far from the horizon,” he said in his message.

“For, as a young Princess Elizabeth put it in her first ever public broadcast, aged just 14, we can each play our part ‘to make the world of tomorrow a better and happier place’. It is a belief which I share, with all my heart.” Charles did not specify the troubles to which he was referring.

The message comes after his brother Andrew Mountbatten-Windsor was stripped of his titles over his association with the convicted sex offender Jeffrey Epstein. The global economy is facing uncertainty after the US and Israel’s war against Iran, which has triggered spikes in the oil price and affected global shipping, while Russia’s invasion of Ukraine has entered its fifth year.

Elizabeth died peacefully at her Balmoral home aged 96 on 8 September 2022 after serving as sovereign for 70 years. In the video tribute, filmed in the library at Balmoral Castle in early April, the king said: “Her near-century was one of remarkable change and yet, through each passing decade, through every transformation, she remained constant, steadfast and wholly devoted to the people she served.