The Last Night of the Proms and the Mercury Music Prize ceremony have been called off following the news of the death of Queen Elizabeth II.
The traditional finale of the Proms season was due to take place at the Royal Albert Hall on Saturday.
Organisers said the event had been cancelled as a mark of respect.
The Mercury Music Prize ceremony was due to take place on Thursday but was postponed after nominees had started arriving at the London venue.
Artists including Sam Fender and Little Simz had already arrived and rehearsed for the show, which was due to be screened on BBC Four, when news of the Queen's death was announced.
"Our thoughts and condolences are with The Royal Family at this very difficult time," organisers said in a statement.
The other nominees for the prestigious album of the year award included Self Esteem, Wet Leg, Harry Styles and Gwenno. An announcement about a future date will be made "as soon as we are able", the organisers added.
Thursday night's Proms concert was also curtailed, with Alan Davey, controller of BBC Radio 3, making a short announcement from the stage at 19:30 BST.
The Philadelphia Orchestra then played the National Anthem and Elgar's Nimrod, before the concert drew to a premature close.
The Royal Box remained empty and the curtain behind the seats was closed as a mark of respect.
Following the very sad news of the death of Her Majesty The Queen, as a mark of respect we will not be going ahead with Prom 71 on Friday 9 September, or the Last Night of the Proms on Saturday 10 September.
— BBC Proms (@bbcproms) September 8, 2022
Meanwhile, the Royal Opera House cancelled the opening night of its new production of Mozart's Don Giovanni.
"We are enormously saddened to learn of the death of Her Majesty Queen Elizabeth II," the venue's chief executive Alex Beard said in a statement.
"Her patronage of the Royal Opera House was a source of great pride to all our artists and staff, and her longstanding support for the arts was deeply appreciated."
The Opera House will also close on the day of the Queen's state funeral.
Some theatres dimmed their lights on Thursday but most other performances went ahead as planned, including the Royal Shakespeare Company's productions of Richard III in Stratford-Upon-Avon and Matilda The Musical in London.
In a statement, the company quoted a passage from Shakespeare's Henry VIII, about the baby princess Elizabeth I: "She shall be, to the happiness of England / An aged princess; many days shall see her / And yet no day without a deed to crown it."
"Translated to our times, Elizabeth II sought the happiness of England with her steadfast service, certainly lived many days, and did a great deed on every one," the RSC observed.
In Manchester, the Royal Exchange theatre opened a book of condolence for the Queen, while the Liverpool's Everyman and Playhouse theatres were lit in purple as a mark of respect.