The Archbishop of Canterbury and head of the Roman Catholic Church in England and Wales are among the UK Church leaders praying for the safety and release of two kidnapped bishops in Syria.
Mar Gregorios Ibrahim of the Syriac Orthodox Church and Paul Yazigi of the Greek Orthodox Church of Antioch were abducted by gunmen while carrying out a humanitarian mission on Monday. Their driver was killed.
In a joint statement, the Most Reverend Justin Welby and Archbishop Vincent Nichols said the kidnapping was "another telling sign of the terrible circumstances that continue to engulf all Syrians".
They spoke of their "horror and sorrow" over the escalating violence that has afflicted the country in the last two years and encouraged Christians there to remain in faith despite the challenges.
"We have grieved with all Syrians - with the families of each and every human life lost and with all communities whose neighbourhoods and livelihoods have suffered from escalating and pervasive violence," they said.
"And today, our prayers also go with the ancient communities of our Christian brothers and sisters in Syria."
They called for a political solution to the conflict and for humanitarian aid organisations to be allowed access to all who are suffering.
"We both continue to pray for a political solution to this tragic conflict that would stem the terrible violence and also empower all Syrians with their fundamental and inalienable freedoms," they said.
"We pray that Syria can recapture its tradition of tolerance, rooted in faith and respect for faiths living side by side."
There were early reports that the two men had been released the day after their abduction but these have been confirmed as false by church officials.
The Primate of the Diocese of the Armenian Orthodox Church in the UK and Ireland, Bishop Vahan Hovhanessian, said he felt "deep sadness and much pain" over the kidnappings.
He called upon governments to help secure the church leaders' release and bring the perpetrators to justice.
"Such acts of terrorism further destroy the fabric of the community in the Middle East which for centuries has been used to having the adherers of the three monotheistic religions living harmoniously and peacefully with each other," he said.
"We call on our brothers and sisters of all peace-promoting religions to denounce this act of terrorism and pray for the safety of the kidnapped bishops.
"We ask the leaders of the democratic countries around the world to condemn this act of terrorism and pursue the perpetrators, securing the harmless homecoming of these two clergymen."