On King Charles III first visit to Northern Ireland, he told politicians his late mother Queen Elizabeth "never ceased to pray for the best of times" for the nation.
The monarch, who visited Hillsborough Castle as part of his day in Northern Ireland, also received a message of condolence from the speaker of the Assembly.
It was read by Sinn Féin's longest-serving elected representative, Alex Maskey and was quite complimentary about the new monarch.
He said the Queen recognised how a "small but significant gesture can make a huge difference in changing attitudes".
Speaking at Hillsborough Castle, the King said: "In the years since she began her long life of public service, my mother saw Northern Ireland pass through momentous changes and historic changes.
"Through all those years, she never ceased to pray for the best of times for this place and it's people.
"Whose stories she knew, whose sorrows her family had felt and whom she had a great affection and regard for.
"My mother felt deeply, I know, the significance of the role she herself played in bringing together those who history had separated and extending a hand to make possible the healing of long-held hurts.
"Now, with that shining example before me, and with God's help, I take up my new duties resolved to seek the welfare of all the inhabitants of Northern Ireland."
The King also held private meetings with Northern Ireland Secretary Chris Heaton-Harris and senior representatives from Stormont's political parties.
Crowds gathered to greet the King and Queen Consort Camilla upon his arrival to the castle.