Catholic, Baptist, Methodist and Pentecostal churches have all joined the Thy Kingdom Come initiative which Justin Welby has spearheaded.
Writing on Twitter on Thursday, he said: "Today, Thy Kingdom Come begins. Join me in praying for people we know to come to faith in Jesus Christ. Come Holy Spirit!"
Believers from every continent are being encouraged to ask God to move in the lives of friends, family members, neighbours and colleagues who do not yet know Christ.
Rev Canon Chris Russell, an evangelism advisor at Lambeth Palace told Premier: "We've all got friends who long would know the transforming love of Christ.
Today Thy Kingdom Come begins. Join me in praying for people we know to come to faith in Jesus Christ. Come Holy Spirit! pic.twitter.com/Ssy7YVRZmi
— Archbishop of Canterbury (@JustinWelby) May 10, 2018
"All of us know people whose lives would be completely different if they knew of Jesus and so this is an opportunity in these ten days to say 'pray in this concentrated manner...'"
"The five friends that I'm praying for in these next ten days, God absolutely [and] passionately loves and so, when I bring these people to Him and ask him to impact their lives, then He answers those prayers."
Click here to listen to Premier's John Pantry and Rosie Wright speaking with Rev Canon Chris Russell:
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