Sinn Féin vice-president Michelle O’Neill has told King Charles III she hopes the British-Irish relationship "strengthens and evolves".
Ms O'Neill expressed her sympathies over the death of Queen Elizabeth II as Stormont party representatives met the new monarch at Hillsborough Castle in Co Down.
She told him: "Her life and legacy will be fondly remembered by those of a British identity here who with great pride and devotion held her very dear.
Read more: NI secretary wants to 'deliver enough pressure' to restore Stormont and fix Brexit Protocol
"She led by example in advancing peace and reconciliation and the building of relationships with those of us who are Irish, and who share a different political allegiance and aspirations to herself and her Government.
"I hope this continues now that you are King and the British-Irish relationship strengthens and evolves as one era ends, and a new one begins in these changing times."
DUP leader Sir Jeffrey Donaldson welcomed the attendance of all Stormont's main political parties at Hillsborough Castle, saying it was a "recognition that the King has a role in reconciliation here".
"He has demonstrated a very sharp insight into Northern Ireland and shown a great interest in the development of Hillsborough Castle," the Lagan Valley MP said.
"He is sensitive of political differences here and keen to build on reconciliation."
Sir Jeffrey added: “There are lots of people here today, here to welcome their new head of state.
"There is a lot of interest in the monarchy here in Northern Ireland."
Ulster Unionist leader Doug Beattie said it was an "immense honour" to welcome the King and Camilla, the Queen Consort, to Northern Ireland.
He said: "This is a moment in history, a time to reflect and remember the glorious reign of Her Majesty Queen Elizabeth II and at the same time look forward with confidence to the future.
"As the leader of the Ulster Unionist Party, I offered my condolences to the King and pledged the allegiance of the party, as we did 70 years ago on the accession of Queen Elizabeth II to the throne."
He added: "In the same way that King Charles said that Her Majesty Queen Elizabeth II wished the best for the people of Northern Ireland, we wish the King and the Queen Consort the very best for the future."
King Charles pledged to "seek the welfare" of all Northern Ireland's people and described how his family have felt their “sorrows” as he praised his mother's relationship with Northern Ireland.
Charles, who in 2015 visited the site of his great-uncle Lord Mountbatten’s murder in an IRA bombing, said the Queen had "never ceased to pray for the best of times for this place and its people".
The new monarch said the late Queen was aware of her position in bringing together divided communities "whom history had separated".
The King was responding to a message of condolence on behalf of the people of Northern Ireland from the Stormont Assembly Speaker, Sinn Fein's Alex Maskey.
Speaking ahead of the meeting with the King, Alliance leader Naomi Long said the late monarch's ability to build bridges was an important legacy to celebrate.
She told the BBC: "The graciousness and the generosity of her own personal actions despite her own personal loss as part of the Troubles here I think has kind of transcended people's issues of the monarchy and whether or not they are royalists.
"People can recognise I think greatness in a person irrespective of those issues."
READ NEXT:
- NI secretary wants to 'deliver enough pressure' to restore Stormont and fix Brexit Protocol
- 10-year stalemate over Maze prison site redevelopment 'a monument to political failure'
- Review proposes Stormont policy change after row over Queen's Platinum Jubilee tree
- No action to be taken over Sinn Féin Irish-language road signs, Stormont department says
For all the latest news, visit the Belfast Live homepage here. To sign up to our FREE newsletters, see here.
