Church leaders are uniting for a 15-state "moral revolution" in America, to champion the Christian values of love, justice and mercy in the country's politics.

"In working toward a spiritual and political renewal of the nation, our multi-state tour is focused on a revolution of moral values," said Rev James Forbes, minister of New York's Riverside Church, and co-organiser of the event.

"By morality, we mean governing for the good of the whole, not for the good of a destructive few. In the tradition of the great prophets, a revival is about stirring up the faithful; restoring believers to a place of maximum impact. Our tour is about preparing leaders of faith to go to the public square and provide a strong moral voice and witness against the extremists' rhetoric and policies."

The tour, called 'The Revival: Time for a moral revolution of values' will begin on Sunday April 4 and end in January next year. It will go to 15 states – North Carolina, South Carolina, Georgia, Alabama, Mississippi, Indiana, Wisconsin, Minnesota, Pennsylvania, Ohio, Tennessee, Virginia, Texas, Oklahoma, and Washington DC.

The tour, organised by Repairers of the Breach, Healing of the Nations Ministries, and Drum Major Institute, hopes to engage clergy and others to organise at state capitals and at key political events during the election.

The tour will comprise of training in "moral political organising" and revival services to change the conversation in politics at a national and local level.

"Way too much of our national discourse has been poisoned by hateful language and policies," said Rev William J Barber II, the founder of the Moral Mondays movement.

"True faith and true evangelicalism place love, justice and compassion at the centre of our public life."

Social justice activists will be joining the tour, including Rev Traci Blackmon, who has worked with Black Lives Matter, and Sister Simone Campbell, who founded the nuns on a bus movement.

"Many Pentecostals focus on the outpouring of the Holy Spirit as detailed in the biblical chapter, Acts 2. But as Christians and people of faith, we are compelled to put our faith in action and work to heal the ills of our society. Faith of and by the Spirit begins with Good News (evangel) to the poor and dispossessed over against the systems of injustice," said Forbes in a statement.

"The Revival will help bring an end to oppressive governmental policies that threaten public education, impoverish millions, block access to health care, and erect new barriers to voting and political participation, threatening the fabric of American democracy," said Barber.

The tour will begin at a Reform synangogue in Raleigh, North Carolina, on the anniversary of Martin Luther King Jr's assasination in 1968, and his sermon at the synagogue a year before.

"Dr. King brought the civil rights movement as far as he could. My job is to join Dr. King and use the power of the gospel and the Holy Spirit as a means of transforming the individual and society," said Forbes.

"In reference to the Vietnam War in his 1967 sermon, Dr. King told the nation that 'silence was betrayal,'" Barber said. "If silence was betrayal in the 1960s, revival is a necessity in 2016."