Dr Rowan Williams, Archbishop of Canterbury, has written to military chaplains and soldiers serving in the Gulf.
The letter, written before the start of the war and sent from Lambeth Palace, reads:
"Amidst all the preparations for armed conflict possibly involving British military personnel, I wanted, in the light of my own pastoral responsibilities, to write to assure you and those under your care of my thoughts and prayers in these difficult and testing times.
"There has been a great deal of public discussion about the events now unfolding; the decisions that have been made have been hard choices between different kinds of risk and cost.
'Hard and dangerous places'
"But that is not the focus of this letter and we pray for those who carry the great burden of responsibility for making key judgements in these matters.
"Those who are deployed with their units will, I am certain, acquit themselves with courage and dedication.
"Few join the armed forces without having thought deeply about the personal cost of service or of the possibility of being put in harm's way and the Church has never shrunk from sending its clergy to serve as chaplains wherever military people find themselves.
"You stand in a long and honourable tradition of Christians bearing witness to the love of Christ in hard and dangerous places.
'Swift and safe return'
"You and I are both charged, in our different ways, with the pastoral care of members of the armed forces and their families.
"As you exercise your ministry with them, please be assured that prayers are being offered here for you and those under your care.
"We pray for your swift and safe return.
"Every blessing, Rowan CANTUAR."