ISTANBUL — Pope Francis and his counterpart in the Orthodox Church on Sunday vowed to work together to prevent an exodus of Christians from the Middle East, and they called for “constructive dialogue” with Muslims to resolve conflicts in the embattled region and around the world.

“We cannot resign ourselves to a Middle East without Christians, who have professed the name of Jesus there for two thousand years,” the pope and Ecumenical Patriarch Bartholomew of the Orthodox Church said in a common declaration issued here on the last leg of a three-day papal visit to Turkey.

The pope made frequent mention on his trip of the plight of Christians and other minorities in areas of Syria and Iraq who have been the focus of persecution by the Islamic State.

His attention to the issue was highlighted in a meeting with a group of young Christian and Muslim refugees from Syria, Iraq and Africa at the Holy Spirit Catholic Church in Istanbul. Pope Francis listened as an Iraqi Christian girl described the refugees’ sufferings and expressed gratitude for his visit.