After a historic meeting in Havana, Roman Catholic Pope Francis and Russian Orthodox Patriarch Kirill signed a joint declaration on religious unity Friday, the Associated Press reported. The declaration covered Christian beliefs and current conflicts as it called for peace in Iraq, Syria and Ukraine.

The leaders of the Roman Catholic Church and the Russian Orthodox Church had not spoken since 1054 when the Great Schism divided the eastern and western Christian churches. In the declaration, the two leaders called for Europe to “remain faithful to its Christian roots,” while directing attention to countries in the Middle East and Africa where Christians face persecution.

“In our determination to undertake all that is necessary to overcome the historical divergences we have inherited, we wish to combine our efforts to give witness to the gospel of Christ and to the shared heritage of the church of the first millennium, responding together to the challenges of the contemporary world,” the two leaders said in their joint declaration.

Pope Francis said his meeting with Patriarch Kirill was clear and direct, adding, “I greatly appreciate his desire for unity.” The Russian Orthodox Church had criticized the Roman Catholic Church for proselytizing in Eastern Europe during the 1990s in countries it considers within its own sphere of influence, including Belarus and Ukraine.

The historic meeting, which took two years of secret planning to arrange, was criticized by some because of Kirill’s close ties to Russian President Vladimir Putin. Kirill famously called the Russian president “a miracle of God,” and the Russian Orthodox Church has been supported by oligarchs aligned with Putin, Reuters reported.

Russia has been suffering under Western economic sanctions imposed due to its annexation of Crimea in 2014 and the ongoing conflict in eastern Ukraine that has left more than 9,000 people dead. Meanwhile, Ukraine has its own Orthodox Church under the patriarchate in Kiev.

“It is our hope that the schism between the Orthodox faithful in Ukraine may be overcome through existing canonical norms, that all the Orthodox Christians of Ukraine may live in peace and harmony, and that the Catholic communities in the country may contribute to this, in such a way that our Christian brotherhood may become increasingly evident,” Francis and Kirill said in their statement.

After the meeting with the patriarch, the Argentine-born pope embarked on a five-day visit to Mexico, where he will focus on poverty, immigration and corruption. The pontiff will celebrate Masses in Chiapas, close to the border with Guatemala, and in Ciudad Juárez, near the border with Texas.