The attendants, which included all of the six living ex-British prime ministers, repeated the phrase.
Laing stated in her tweet that the flags will return to half-mast after 1pm on September 11 and remain in that position until 8am on the day after the funeral of Queen Elizabeth II.
The tweet read: “From 9am on 10th September to 1pm on 11th September flags on UK government buildings around the world will be raised to mark the accession of King Charles III to the throne before returning to half-mast until 8am on the day after the funeral of Her Late Majesty Queen Elizabeth II.”