LEICESTER, United Kingdom – Cardinal Vincent Nichols, the Archbishop of Westminster, and the Archbishop of Canterbury, Justin Welby, have sent a joint letter to Israel’s Ambassador to the United Kingdom, urging the Israeli government to protect the “Status Quo” of holy sites in Jerusalem.

The appeal came after an attempt by the Jerusalem mayor to tax Church-owned sites in the city, a move the Catholic and Anglican leaders called unprecedented, punitive and discriminatory.

“[The proposed taxes] threaten to cause serious damage to the Christian presence in Jerusalem, to Christian families, and to the Christian institutions, including hospitals and schools, which serve many of the poorest people, regardless of their background,” the letter reads.

“It is our view that the measures being pressed in Jerusalem and in the Knesset are a clear and evident threat to the status quo. These violations of historic agreements risk undermining prospects for peaceful coexistence between communities, at a time of already heightened tensions,” the letter continues.

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Israeli Prime Minister Benjamin Netanyahu established a team on Feb. 27 to negotiate with church officials to “formulate a solution,” after the mayor suspended the tax plan.

Some observers said the step appeared to be an escalation in a dispute between Jerusalem Mayor Nir Barkat and Israel’s central government about funding for the city. The mayor said the taxes would only apply to church-owned institutions not used for worship, such as hotels, restaurants, and conference centers.

The heads of churches in charge of the Holy Sepulcher and the Status Quo governing the various Christian Holy Sites in Jerusalem – the Greek Orthodox Patriarchate, the Custody of the Holy Land and the Armenian Patriarchate – closed the Church of the Holy Sepulchre – which is the site of the passion and burial of Christ – for several days to protest the tax decision. It was reopened on Feb. 28.

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The “Status Quo” is an arrangement guaranteed by the Ottoman government in the 18th and 19th centuries laying out who controls aspects of seven sites in Jerusalem and two sites in Bethlehem.

Seven of these sites are Christian, and responsibility is shared between different churches, and two – the Western Wall/Noble Sanctuary in Jerusalem, and Rachel’s Tomb in Bethlehem – are shared between Jews and Muslims.

Under the Status Quo, even the smallest change to any site must be approved by all the involved parties.

Last summer, deadly riots broke out in Jerusalem after Israel tried to install metal detectors at one of the sites – the Western Wall/Noble Sanctuary – unilaterally.