The Prime Minister will pay tribute to the “remarkable” Queen in an address to Parliament ahead of her Platinum Jubilee.
Boris Johnson will say that the Queen’s length of service and dedication to duty are “without parallel”.
It comes as the nation prepares to celebrate the Jubilee over the June bank holiday.
The four-day bank holiday weekend will see a service of thanksgiving at St Paul’s Cathedral, the Platinum Party at the Palace and the Platinum Jubilee Pageant.
Mr Johnson will make his tribute to the Queen while proposing a Humble Address in Parliament.
He will say: “Today we pay tribute to a head of state whose length of service and dedication to duty to are simply without parallel.
“The only monarch most of us in this country have ever known and the rock to which our nation and our people have been anchored throughout all that the past 70 years have thrown at us.”
He will add that the people of the United Kingdom and the Commonwealth will be “unabashed” in celebrating her.
“That is why next week the people of the United Kingdom and the Commonwealth will be unabashed in celebrating not the institution of the Crown but the individual who wears it,” he will tell Parliament.
“This remarkable woman who by God and her right has led her country through good times and bad.
“Who has dedicated her life to her people, to her beloved Commonwealth, to the very idea of what a constitutional monarchy can and should be.”