They were speaking after receiving reports from Iraq, Iran, Egypt, India, Pakistan and Indonesia.
The leaders have called upon all people to respect the "sanctity of life and the flourishing of every human being."
They have also stressed the fundamental God-given right and freedom to practice faith, and called for the peaceful co-existence of different religious groups.
The presidents also remembered Archbishop Oscar Romero of El Salvador, who was assassinated while celebrating Mass in 1980.
The prayer says: "Almighty God,
"You called your servant Oscar Romero to be a voice for the voiceless poor, and to give his life as a seed of freedom and a sign of hope: grant that, inspired by his sacrifice and the example of the martyrs of El Salvador, we may without fear or favour witness to your Word who abides, your Word who is Life, even Jesus Christ our Lord, to whom, with you and the Holy Spirit, be praise and glory now and for ever.
Amen."
