The day will begin with Boris Johnson’s final farewell speech in Downing Street on Tuesday at 7.30am.
He will then travel to Balmoral in the Scottish Highlands to formally tender his resignation to the Queen before Liz Truss arrives.
After Mr Johnson, Ms Truss will meet the Queen, who will be formally invited to form a government.
She will then return to Westminster, where she is expected to address the nation for the first time as Prime Minister around 4 p.m., before starting to appoint her ministerial team.
Some key allies and supporters have been appointed to some of the highest positions.