The Rev Yemi Adedeji is pastoral aide to the senior pastor at Jesus House in London, one of the largest black-majority churches in Britain.
He has been appointed as an Associate Director of HOPE and will be consulting for the mission movement, as well as building up networks and bringing different church networks and denominations together for the purpose of united mission.
It is hoped that his appointment will strengthen partnerships with black-majority churches and networks.
Rev Adedeji said: "I get excited about the HOPE vision – particularly unity for the purpose of mission.
"The black-majority churches do things a little differently but I have a passion for allowing churches of every tradition, culture and style to work together in their communities.
"There are huge opportunities for the diverse church throughout the UK to make an impact in our nation."
HOPE was launched last July during an all-night prayer gathering hosted by the RCCG in London. It sprang out of HOPE 08, a yearlong movement which saw churches in 1,500 areas work together to be the good news in their local communities.
Senior pastor of Jesus House, Pastor Agu Irukwu, said he was "delighted" that Rev Adedeji would be working to deepen partnerships across the UK church.
"We dream of a time when Baptists, evangelicals, Methodists, Pentecostals, charismatics, Catholics, Free Church, Anglicans and so many more will all come together, no matter what background they are from," he said.
"They will come together and be the church – a church without walls that is making an impact."
Rev Adedeji is also an ordained Anglican minister and has previously worked for Church Mission Society.
He became the first African trustee/director at the Anglican mission agency in its 210-year history and served as Outreach and New Relationship Adviser to over 2,000 Anglican churches in the UK as well as to mission outlets around the world.
Roy Crowne, Executive Director of HOPE said: "We are thrilled to have Yemi as part of our team to help us develop a larger strategy to encompass more denominations and cultures to do more together, in words and actions and answer the call to relevant mission.
"We need to celebrate diversity and understand that we have strengths when we work together for the sake of those outside of the kingdom."
Bishop Wayne Malcolm, senior pastor of Christian Life City Church and a member of the HOPE leadership team, said that the desire to collaborate across denominational, ethnic and cultural lines for the purpose of evangelising Britain was "unprecedented and exciting".
He said: "This appointment is a significant step towards realising the dream of a united church working together to reach our divided country."