Downing Street are urging the public to pause at 8pm on September 18 to consider the late monarch’s legacy.
The announcement was made on Monday morning shortly after Charles III addressed Parliament for the first time as King.
The Prime Minister’s official spokesman said: “At 8pm on Sunday, September 18, the night before the state funeral, there will be a one-minute silence where the public are invited to come together and observe a national moment of reflection to mourn and reflect on the life and legacy of Queen Elizabeth II.
“The silence can be marked privately at home on your own or with friends and neighbours, out on your doorstep or street with neighbours, or at any locally arranged community events and vigils.
“We encourage local community groups, clubs and other organisations to mark this moment of reflection. And if you are overseas, people are encouraged to mark the silence at their local time.
“The shared national moment of reflection is an opportunity for everyone across the UK to mark the death of Her Majesty and we will set out details of where the Prime Minister will mark it closer to that time.”
The Prime Minister’s official spokesman said: “At this point we can’t be more specific on numbers.
“I think for the Queen Mother it was around 200,000 people [who attended], we expect [it] to be far more than that for this lying in state. But at this point, but we can’t be more specific into exact numbers.”
On whether commuters should work from home this week if they normally travel into the capital from outside London, the spokesman said some people “may wish to change their working patterns accordingly”, but acknowledged “not everyone will have that ability”.
Asked if there will be any facilities for people who physically cannot queue for 30 hours, he said: “Obviously we want everyone to be able to attend regardless of whether they have disabilities. Our focus is on ensuring they have the information needed to make the decision about what’s right for them.
“There will be toilet facilities, there will be first aid available, there will be the ability for people obviously to go and use toilets and return to queues and things like that.”
Earlier Commons Speaker Sir Lindsay Hoyle told Westminster Hall that in his first address King Charles “pledged to uphold constitutional principles at the heart of our nation”.
Sir Lindsay said: “In your first address to the nation, you recognised your life would change as a result of the new responsibilities.
“You pledged yourself to uphold constitutional principles at the heart of our nation.
“These are weighty responsibilities. As the early Queen Elizabeth said in her final speech to parliamentarians, ‘to be a king and wear a crown is a thing more glorious to them that see it than it is pleasant to them that bear it’.”