The Queen is to address both Houses of Parliament today to mark her 60 years on the throne.
She will speak to an audience of party leaders, MPs, peers and dignitaries in Westminster Hall before unveiling a stained glassed window specially commissioned for the Diamond Jubilee.
Events to mark the Queen's 60-year reign began in February.
Celebrations for the Diamond Jubilee will come to an end in June during a four-day series of events.
In her speech, the Queen will respond to tributes made to her in both Houses of Parliament earlier this month.
David Cameron, Nick Clegg and Ed Miliband - as well as former prime ministers - will be among those in attendance.
The tradition of both houses of Parliament making addresses to the monarch and the sovereign replying dates back to the 16th Century.