The Queen will urge Britain to prove that this generation is "as strong as any" in her address to the nation, amid fears the current warm weather will see people flout the coronavirus social distancing rules.
In a televised message to be broadcast on Sunday evening, the Queen will recognise the pain felt by many families living through this "time of disruption".
She will personally thank front-line NHS staff, care workers and others carrying out essential roles for their efforts, in what is expected to be a deeply personal message reflecting her experience in other difficult times.
It comes as the UK death toll from the virus rose by 708 - bringing the number of coronavirus-related hospital deaths to 4,313 as of 5pm on Friday, up from 3,605 the day before. A five-year-old child was among the victims.
Prime Minister Boris Johnson and Cabinet Office minister Michael Gove have reiterated calls for Britons to obey the social distancing rules despite the warm weather, but some parks closed on Saturday as too many people flouted the advice to stay at home.
Mr Gove said seven healthcare professionals have now lost their lives during the coronavirus outbreak as he urged people to stay inside over the weekend to ensure their sacrifice had not been in vain.
His call came as:
- Professor Stephen Powis, NHS England's national medical director, warned that while new cases of coronavirus appear to have stabilised, now is not the time to "take our foot off the pedal".
- John Alagos, a 23-year-old NHS nurse, died after treating patients with coronavirus, his mother told the Mail on Sunday.
- Carrie Symonds, Mr Johnson's pregnant fiancee, said she had spent the last week in bed suffering coronavirus symptoms, but was "on the mend".
- The chairman of the Doctors' Association Rinesh Parmar told the Sun on Sunday he feared more than 50 doctors could die "if the PPE dries up and we have no choice but to treat our patients without the right equipment".
- The Ministry of Justice said hundreds of risk-assessed prisoners within two months of their release date are to be temporarily sent home to reduce the chance of coronavirus taking hold in jails and overwhelming the NHS.
- Newly-elected Labour leader Sir Keir Starmer accused the Government of making "serious mistakes" in its response to the coronavirus crisis, but pledged to engage "constructively" with ministers.
The Queen will say in her address to the country and Commonwealth: "I hope in the years to come everyone will be able to take pride in how they responded to this challenge.
"And those who come after us will say that the Britons of this generation were as strong as any.
"That the attributes of self-discipline, of quiet, good-humoured resolve and of fellow feeling still characterise this country."
She will acknowledge the "grief" some have experienced, the "financial difficulties" many face, and the "enormous changes" the country is enduring, after almost two weeks of lockdown to tackle the spread of Covid-19.
With hundreds of thousands answering the call for NHS volunteers and others supporting vulnerable people in their communities, the monarch will say she hopes in the future everyone will be able to feel "pride" in how they rose to the challenge.
Commenting on the difficulties facing the nation, the Queen, 93, will say: "I am speaking to you at what I know is an increasingly challenging time.
"A time of disruption in the life of our country: a disruption that has brought grief to some, financial difficulties to many, and enormous changes to the daily lives of us all."
In reference to the warm weather, the Queen will thank those who are following the official guidance to stay at home to protect the vulnerable.
The televised address will be a rare event, with the head of state only making three previous appearances during troubled times.
Speeches were broadcast after the Queen Mother's death in 2002, ahead of Diana, Princess of Wales's funeral in 1997, and about the first Gulf War in 1991.
It was recorded at Windsor Castle under special circumstances after specific advice from the Medical Household was sought, and followed, to mitigate any risk to the Queen and others.
The castle's White Drawing Room was specifically chosen so an appropriate distance could be maintained between the Queen and the other occupant - a cameraman wearing personal protective equipment.
The Queen has been staying at her Berkshire home of Windsor Castle with the Duke of Edinburgh since March 19, arriving earlier than normal for the Easter period as a precaution amid the pandemic.