YEREVAN (Reuters) - Pope Francis said on Friday (June 24) that Britain's decision to leave the European Union must be followed by "guarantees" for the good of both Britain and countries on the continent.

"It was the will expressed by the people and this requires a great responsibility on the part of all of us to guarantee the good of the people of the United Kingdom, as well as the good and co-existence of the European continent," he said.

"This is what I expect," he said, adding that he had been told the definitive result when he boarded the plane in Rome.

Pope Francis, who was beginning a weekend visit to Armenia, normally takes questions from journalists only on the return flight of his trips but made an exception this time, clearly eager to speak about the seismic Brexit referendum.

Speaking shortly after leaving Rome for the Armenian capital, Yerevan, Pope Francis suggested the referendum result - 51.9 per cent to 48.1 per cent in favour of leaving the EU - had to be respected because it represented the popular will.

The Vatican has always strongly supported the European Union.

Pope Francis, the first pope from Latin America, also expressed satisfaction at a ceasefire agreement between Colombia's government and FARC guerrillas brokered by Cuba. He said the accord should be made "ironclad so that there will be no going back to a state of war".

In Armenia, which in the 4th century became the first nation to adapt Christianity as a state religion, Francis is expected to avoid the word "genocide" so as not to reignite a dispute with Turkey sparked last year when he used it to describe the 1915 mass killings of some 1.5 million Armenians.

Turkey promptly recalled its ambassador to the Vatican and kept him away for 10 months.

Turkey accepts that many Christian Armenians living in the Ottoman Empire were killed in clashes with Ottoman forces during World War One, but it contests the figures and denies that the killings were systematically orchestrated and constitute a genocide. It also says many Muslim Turks perished at that time.

The Armenian Apostolic Church, whose leader is known as the"Catholicos", split from Rome over a theological dispute in the fifth century and is part of the Oriental Orthodox Churches. It is seen as the custodian of Armenian national identity.

As the Pope visited Yerevan's cathedral, Catholicos Karekin II used the word genocide at least three times in his address, while Francis referred to the "martyrdom" Armenians suffered in the course of their history.