“Her Majesty The Queen has recorded a special broadcast to the United Kingdom and the Commonwealth in relation to the coronavirus outbreak,” Buckingham Palace said in a statement.
The address, which was recorded at Windsor Castle where the 93-year-old monarch is hibernating with her husband Prince Philip, will be broadcast at 1900 GMT on Sunday.
The news came as the death toll among those who had tested positive for the virus rose on Friday by 684 to 3,605, up 23% on the previous day.
The death toll escalated despite government putting the country into a virtual lockdown.
Pubs, restaurants and nearly all shops are closed.
Government also banned social gatherings and ordered Britons to stay at home.
Last month, the queen issued a statement in which she said the royal family rise to the challenge of the outbreak.
“We know that many individuals and families across the United Kingdom, and around the world, are entering a period of great concern and uncertainty,” she said then.
“We are all being advised to change our normal routines and regular patterns of life for the greater good of the communities we live in and, in particular, to protect the most vulnerable within them.”
The queen rarely broadcasts to the nation apart from her annual televised Christmas Day message, usually to offer personal thanks or provide reassurance in times of crisis.
Royal experts said it would be only the fifth such televised address she had made during her 68 years on the throne.
The last was in 2012 following celebrations to mark her 60th year as queen.
She used the broadcast to thank Britons for their messages of condolence.
She also gave an address at the start of the Gulf War in 1991.
Most famously, she delivered a sombre live broadcast after the death of her daughter-in-law Princess Diana in a Paris car crash in 1997.
The broadcast came amid a national outpouring of grief and criticism of the royal family.