On April 10, 2025, the Holy Synod of the Russian Orthodox Church issued a statement opposing a law passed by the Estonian Parliament, which, according to the document, violates religious freedom and threatens the future of the Estonian Orthodox Christian Church — a self-governing body within the Moscow Patriarchate.

In response to the situation, Patriarch Kirill of Moscow and All Rus’ sent official appeals on April 11 to the Primates of Orthodox Churches, leaders of Christian denominations, international organizations, and heads of state.

The letters emphasize that the amendments adopted in Estonia to the law on churches and congregations effectively outlaw the Estonian Orthodox Church of the Moscow Patriarchate. This, the Patriarch stated, violates the Estonian Constitution and international standards that guarantee freedom of religion. Patriarch Kirill expressed deep concern over the developments and called for fraternal support.

"With deep concern, I inform you that on April 9, 2025, the Estonian Parliament passed amendments to the law on churches and congregations, aimed at effectively banning the Estonian Orthodox Christian Church — a self-governing Church within the Moscow Patriarchate. The law, which strips the Church of its legitimacy, violates the fundamental principle of freedom of conscience and religion, guaranteed by the Estonian Constitution and relevant international agreements," reads the Patriarch’s appeal.

Recipients of the letters include the Patriarchs of Antioch, Jerusalem, Serbia, Romania, and Bulgaria; the Catholicoi of the Armenian and Assyrian Churches; the Archbishops of Poland, Albania, the Czech Lands and Slovakia; the Primates of the Orthodox Church in America and the Macedonian Orthodox Church, as well as Pope Francis, Coptic Patriarch Tawadros II, and other religious leaders.

Letters were also sent to political figures known for their advocacy of Christian rights, including Serbian President Aleksandar Vučić, Hungarian Prime Minister Viktor Orbán, and U.S. President Donald Trump.

Additionally, Patriarch Kirill appealed to the Secretaries-General of the UN, OSCE, and the Council of Europe, as well as representatives of international human rights organizations, including special rapporteurs on religious freedom and discrimination. The Patriarch included the full statement of the Holy Synod from April 10 as an attachment to his letters.