As the battle over Syria's largest city has raged for more than two years, the Community of Sant'Egidio on Tuesday launched a campaign for international solidarity to promote a truce in the historic metropolis.

Andrea Riccardi, founder of the lay association known for its dedication to peace, said Nov. 18 that "Aleppo, a world of cohabitation, where Christians and Muslims lived together, is going to be destroyed. It is not a battle. It is an agony."

The appeal for Aleppo included the launch of the hashtag #savealeppo to draw attention to the city's plight.

The Sant'Egidio community's president, Marco Impagliazzo, was recently received at the United Nations by its secretary general, Ban Ki-moon, "who gave his support to the Sant'Egidio initiative," said Riccardi.

The Sant'Egidio community has played a leading role in successfully negotiating for peace in previous conflicts, including in Senegal in 2012; Algeria in 1995; and Mozambique in 1992.

The battle of Aleppo began in July 2012  as part of the Syrian civil war. It has involved the Syrian regime and its ally Hezbollah; moderate rebels such as the Free Syrian Army; Islamist rebels such as al-Nusra Front and Islamic State; and Kurdish forces.

"Each of these forces may surround the other; the battle is completely balanced, and people are completely stuck in the middle, while public opinion has almost forgotten what it is going on in Syria," maintained Riccardi.

Riccardi blamed the lack of interest on the Syrian situation on the fluctuation of public opinion, which "easily forgets," as has happened with the plight of Christians in Iraq.

According to Riccardi, "there are now about 1 million people in Aleppo, but it is difficult to assess with precision how many Christians have remained … perhaps there are 60 thousand left."

The city is divided into zones held by the regime, Kurds, and rebels, with an estimated 300,000 persons in rebel-held areas.

In 2005, before the war began, the city's population was estimated at 2.3 million.

The Sant'Egidio community does not want to give diplomatic suggestions, but it hopes "that the situation of Aleppo would be frozen, and eventually that there is an international intervention coordinated by the United Nations in order to free Aleppo and make of Aleppo an 'open city' on the model of Rome during the Second World War."

In August 1943, Italian forces declared Rome an "open city," saying they had abandoned the city's defense in the face of Allied advances. The city was eventually liberated in June, 1944, without bloodshed.

In Aleppo, "many now predict it is just a matter of time" before the city falls to the Syrian regime if no ceasefire is signed, the BBC's Lyse Doucet wrote Nov. 14. "Syrian troops are encircling (the rebel-held zone) in a pincer movement to cut supply lines, an attempt to force surrender and defeat," she continued.

Sant'Egidio's proposal for a 'freeze zone' in Aleppo has been accepted by Staffan de Mistura, the United Nations envoy to Syria.

The freeze zone plan would institute local truces in the Syrian civil war, allowing the delivery of humanitarian aid in a war that has killed at least 200,000 and forced more than 11 million from their homes.

But it is feared that the Syrian regime will not continue advancing in Aleppo unless the freeze zone is situated to its clear advantage.

Aleppo was chosen for the ceasefire "as a symbol, because Aleppo has been the biggest city of cohabition among religions," said Riccardi.

"I remember when the bells of Christian churches rang along with the Muslim muezzin. There, the Arabic world, Kurdish world, Armenian world, and Christian world converged, and lived together."

Aleppo has been continuously inhabited since well before Christ, and its Old City was named a UNESCO World Heritage Site in 1986, and in 2006 was named the "Islamic Capital of Culture."

While some 80 percent of its population before the civil war were Muslims, they coexisted well with the city's small Jewish community, and the sizable Christian minority. Large numbers of both Orthodox and Catholics were present, with the city holding the cathedrals of six Catholic bishops of different Churches.

The Community of Sant'Egidio hopes that its efforts at an Aleppo ceasefire will mean rescuing all the religious minorities in the area.

The movement is also organizing a March 5-6, 2015 conference on Christians in the Middle East to be held in Cyprus, which will involve both Christians and Muslims of the region, as well as representatives of international organizations.