The Queen has spoken of the "transformation" of the people of Northern Ireland following the end of the Troubles, as she praised the Colombian president for leading his country along a similar path to peace.
Speaking during a Buckingham Palace banquet held in honour of President Juan Manuel Santos, the Queen said the citizens of Northern Ireland were beginning to "realise their full potential".
The Queen also paid tribute to Mr Santos who has helped broker an historic deal with left-wing Farc (Revolutionary Armed Forces of Colombia) rebels which earned him the Nobel Peace Prize.
Colombia has been blighted by a bitter and bloody internal conflict for decades, as Northern Ireland was before the Good Friday agreement in 1998 paved the way for peace and reconciliation and ended years of sectarian conflict known as the Troubles.
In a lighter moment the monarch thanked the South American leader for a gift of some "world-famous" Colombian coffee which they enjoyed at lunch and would be served tonight and at a palace breakfast business meeting on Wednesday - "Which should ensure that everyone is wide awake".
In the palace's lavish ballroom the Queen told Mr Santos - the first Colombian leader to make a state visit to the UK: "This week you will visit Northern Ireland, which now has one of the largest financial services markets in the United Kingdom outside London.
"Over recent years, I have seen at close hand the transformation of a people held back for so many years by conflict and now, through peace, beginning to realise their full potential."
Although Colombia's peace deal was narrowly rejected by its citizens in a recent vote, the president has extended a ceasefire with the country's largest rebel movement to allow more time for efforts to save the peace deal.
More than 220,000 people - mostly civilians - were killed during the 52-year long conflict and more than eight million were driven from their homes.
The Queen, who wore a pale gold Angela Kelly gown with a George VI sapphire and diamond tiara and matching necklace, said during her address: "The Colombian author Laura Restrepo once wrote, 'War or indifference; it's hard to know which is the hardest to fight' - a phrase which continues to ring true in this uncertain world. It is a reminder that the waging of peace is the hardest form of leadership of all, but also the most rewarding.
"Finding the balance between deeply-held opposing views, while never forgetting the needs of the disengaged, requires patience, resourcefulness and grit.
"Although you have faced recent setbacks, to have come to the cusp of a historic peace agreement, against the expectations of many, is a testament to your courage and perseverance, and that of the Colombian people."
The white-tie dinner featured leading figures from national life including Prime Minister Theresa May, the Duke of Edinburgh, Prince of Wales, Duchess of Cornwall, Mark Carney, the Governor of the Bank of England, tennis star Jamie Murray and his Colombian-born wife Alejandra Gutierrez, and and leading Colombians living in the UK.
Labour leader Jeremy Corbyn did not attend but the Labour Party was represented by shadow foreign secretary Emily Thornberry.
The Queen went on to highlight the strong ties between the UK and Colombia and how the nation's liberator, Simon Bolivar, came to the UK to seek support in the early 19th century and how 200 years later the two countries continued to be close partners.
Her words were echoed by Mr Santos, joined by wife Maria Clemencia Rodriguez de Santos, who told the monarch: "And today we are also grateful for your constant and decisive support in the search of peace for Colombia, and in the upcoming challenging period of the post conflict, so as to ensure a stable and long-lasting peace, after half a century of war."
Mr Santos said: "I am proud - and I say it as someone who has lived in this country and loves it as a second homeland - to be in a position to say that we are allies of the nation who gave humanity the genius of Shakespeare and Dickens; the science of Newton and Darwin; the political boldness of Churchill, and the music of the Beatles and the Rolling Stones."
The 170 guests dined on Dover sole with Morecambe Bay shrimps, followed by pot-roasted Windsor estate pheasant and for d essert was a light mango and passion fruit cream entremet.