Pope Francis is to visit Cairo next month for talks with the grand imam of the capital's famed Al-Azhar mosque, but also to show solidarity with Coptic Christians targeted by violence in Egypt.
The pontiff, co-invited by Egypt's president for the April 28-29 visit, had hosted Grand Imam Ahmed al-Tayeb at the Vatican last May, in a landmark meeting with one of Islam's top clerics.
That encounter was the culmination of a steady improvement in a relationship that had broken down because of a series of spats under Francis's predecessor Benedict XVI.
The current pope has made interfaith dialogue and reconciliation a leading theme of his pontificate and has also overseen an improvement in relations with the Orthodox and Protestant wings of christianity.
The Argentine pope has a long-standing invitation to visit Egypt, issued by President Abdel Fattah al-Sisi when he met Francis at the Vatican in 2014.
The pope will meet both the president and the grand imam, the Egyptian presidency said in a statement.
It added that "this important visit will contribute to reinforcing the message of peace as well as the spirit of tolerance and humanity's dialogue between all the religions and the rejection of... terrorism and fanaticism".
Francis will become the second Roman Catholic pope to visit Egypt, following John Paul II's historic trip there in February 2000.
Relations were derailed under Benedict after rows over a 2006 speech in which he was seen as having linked Islam to violence and 2011 comments condemning an attack on a Coptic church in Alexandria which Al-Azhar denounced as meddling in Egypt's affairs.
- Suicide attack -
Nearly 10 percent of Egypt's 92-million strong population belong to the Coptic community in a country where Sunni Muslims make up the vast majority.
A suicide bomb attack on December 11, claimed by the Islamic State (IS) group, killed 29 people in the Coptic church of Saint Peter and Saint Paul.
The church is next to the Saint Mark's Coptic Orthodox Cathedral -- the seat of Coptic Christian Pope Tawadros II -- which Francis will visit during the trip.
President Sisi condemned the attack, calling it cowardly and declared three days of national mourning. The attack was the deadliest targeting the Coptic community since the January 1, 2011 suicide bombing which killed 23 people in Alexandria.
Since the army overthrew Islamist president Mohamed Morsi, the Sinai peninsula has been hit by almost daily jihadist attacks above all aimed at the police and army.
IS called in a December video for attacks on Coptic Christians in Sinai, in particular in the town of El-Arish in the north of the peninsula.
Seven Coptic Christians have been killed since, while dozens of families have fled the region.
The Cairo visit has been carefully organised by French Cardinal Jean-Louis Tauran, an experience diplomat and energetic promoter of dialogue between the Roman Catholic Church and Islam.
As head of the Pontifical Council for Inter-religious Dialogue, he participated in a February 22 joint seminary with Al-Azhar, the first since 2011.
The theme of the seminary was the role of the Al-Azhar mosque and the Vatican in fighting fanaticism, extremism and violence.
Egyptian Coptic Catholic bishops visited the Vatican in February and had extensive discussions with Francis about their community's concerns.