King Charles has said he and Queen Camilla have "heavy hearts" after Pope Francis's death, as they paid tribute to his "compassion" and "tireless commitment" to people of faith.
The King said in a statement released by Buckingham Palace that though "deeply saddened", their sorrow had been "somewhat eased" by the Pope being able to "share an Easter greeting with the Church and the world he served with such devotion" before he died.
The King and Camilla met the pontiff on a state visit to Italy earlier this month - one of several he said he remembered with "particular affection".
During the private meeting, Pope Francis had wished them a happy 20th wedding anniversary.
The King said: "His Holiness will be remembered for his compassion, his concern for the unity of the Church and for his tireless commitment to the common causes of all people of faith, and to those of goodwill who work for the benefit of others.
"His belief that care for Creation is an existential expression of faith in God resounded with so many across the world. Through his work and care for both people and planet, he profoundly touched the lives of so many."
He also said they had been "greatly moved to have been able to visit him" earlier in April.
The King and Camilla sent their "most heartfelt condolences and profound sympathy to the Church he served with such resolve and to the countless people around the world who, inspired by his life, will be mourning the devastating loss of this faithful follower of Jesus Christ".
Also paying tribute, Prime Minister Sir Keir Starmer said he was joining "millions around the world in grieving the death".
He praised the Pope's leadership of the Catholic Church as "courageous" and coming from a "place of deep humility".
"Pope Francis was a pope for the poor, the downtrodden and the forgotten. He was close to the realities of human fragility, meeting Christians around the world facing war, famine, persecution and poverty," Sir Keir said.
"Yet he never lost the faith-fuelled hope of a better world."
Other senior British politicians to pay tribute include: