Abdel-Fattah el-Sissi, a general-turned-president, has made sectarian harmony a cornerstone of his rule, fighting Islamic militancy while advocating equality between the overwhelming Muslim majority and Christians, who account for ten per cent of Egypt's 100 million people.
"This is a historic and important moment," said Mr el-Sissi inside the cathedral.
"But we still have to protect the tree of love we planted here together today because seditions never end."
The Grand Sheikh of Al-Azhar, the world's primary seat of learning for Sunni Muslims, echoed Mr el-Sissi's sentiments in comments also made at the cathedral.
Excited to see our friends in Egypt opening the biggest Cathedral in the Middle East. President El-Sisi is moving his country to a more inclusive future!
— Donald J. Trump (@realDonaldTrump) January 6, 2019
The two places of worship, he said, stand as a symbol in the face of "attempts to undermine the country's stability and sectarian seditions."
Mr el-Sissi's widely publicised policy to staunch sectarianism, however, has done little to protect Christians in rural Egypt, where Muslim extremists frequently attack their homes and businesses or force them to leave their homes after violent disputes.
السيد الرئيس/ عبد الفتاح السيسي يفتتح مسجد الفتاح العليم وكاتدرائية ميلاد المسيح بالعاصمة الإدارية الجديدة، ويشارك في قداس عيد الميلاد المجيد بالكاتدرائية. pic.twitter.com/TgyJjclZVp
— Ministry of IIC (@MIICEgypt) January 6, 2019
Critics and activists say discrimination against Christians there is often tolerated by local authorities and branches of the security agencies. Christians also complain of stringent restrictions on the construction of churches.
But Sunday's opening ceremony in Egypt's New Administrative Capital, Mr el-Sissi's brainchild that is located in the desert east of Cairo, stressed what the pro-government media like to call the "unbreakable national fabric" of Christians and Muslims.
Entertainers and chorus lines took to the stage to sing about the two faiths living peacefully side by side.
Egyptian President @AlsisiOfficial & Pope Tawadros II, head of Coptic Orthodox Church, at today's inauguration of the largest Cathedral in the Middle East. The new Coptic Cathedral in #Egypt is called the "Cathedral of the birth of Christ." (Pics: Coptic Church Spokesperson) pic.twitter.com/JFWBxa0Uy4
— Iraqi Christian HRC (@iraqschristians) January 6, 2019
Short films on the same topic were also screened.
The ceremony's presenters portrayed the construction of the cathedral and the mosque, which took 18 months to complete, as a message to humanity.
"It is a message to the whole world that Egypt is a nation for all," said one presenter.
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