The Archbishop of Westminster, Cardinal Vincent Nichols, is urging every Catholic to pray that five people they know might become Christians.
In a joint letter with the Archbishop of Canterbury Justin Welby and other church leaders, Cardinal Nichols says: "In particular, can we encourage you to, perhaps, join with us in praying for five particular individuals to make the best decision anyone can ever make in their lives – to become followers of Jesus Christ? Or to pray that in your community, in very specific ways, the love of Christ might be seen and heard so that there will be many whose lives are touched by the grace of God?"
The letter has been issued to mark the Week of Prayer for Christian Unity, from 18 to 25 January.
The church leaders look ahead to the global prayer movement, Thy Kingdom Come, in the run-up to Pentecost in early June when Christians worldwide are urged to pray that more people might hear and respond to the good news of the gospel.
They say: "This week our churches will be praying together for Christian unity in our life together, our witness and our longing to see the Kingdom of God in the midst of our world. We encourage every church to take this call to prayer with the utmost seriousness, and to find ways to give expression to our search for greater unity in obedience to the command of Christ that we love one another.
"Christ prayed that the church might be one, and our striving for greater unity is in obedience to Christ, but unity looks outwards also – it is for the sake of others. We hear this as we listen in to the prayer Jesus prayed the night before he died. He asked his Father to give eternal life to all those given to him, saying ‘this is eternal life, that they may know you, the only true God, and Jesus Christ whom you have sent.' In this same chapter he also prayed for all Christians to be one, as Jesus and his Father are one."
Other signatories include the Rev Michaela Youngson, president of the Methodist Conference, the Coptic Archbishop Angaelos and Pastor Agu Irukwu, chair of the Redeemed Christian Church of God UK.
Cardinal Nichols said: "We should never underestimate the power of prayer nor our need of the strength that God gives us through prayer. I appeal to all to take to heart this Week of Prayer for Christian Unity. Growth in unity comes about, above all, as a gift of God. Our shared life in Christ is the powerful source of our shared mission. May this Week of Prayer, as well as the time of prayer at Pentecost, 'Thy Kingdom Come', strengthen our common life and mission."
Earlier, the Catholic bishops of England and Wales and Church of England bishops met in Leicester from 16 to 17 January for their biennial conference.
Together, the 27 Catholic and 27 Anglican bishops explored a diverse range of subjects including opportunities for closer collaboration at a regional and national level. Cardinal Nichols and Archbishops Welby, along with Archbishop of York John Sentamu, were present throughout.
Dr Paula Gooder and Professor Paul Murray, members of the Anglican Roman Catholic International Commission, led the bishops in reflection on its latest document Walking Together On The Way. The bishops discussed how they might work together to address issues such as the UK’s relationship with the EU.
Archbishop of Birmingham, Bernard Longley said: “This meeting has highlighted how very far we have come in our fraternal discussions in the past 50 years. We have a strong bond, we are dealing with the same problems which we must continue to tackle in our different ways and support each other in our love for Christ and His flock.
"This meeting has been frank and realistic. I am both encouraged and strengthened by this sincere dialogue and our friendship as brothers and sisters in Christ. We journey onwards in hope – we have so much in common – in this drama of redemption.”