Leading conservative evangelicals are condemning a 'white lives matter' protest due on Saturday in Tennessee as 'a work of the devil' and 'an assault against the word of God'.

Christian leaders across the state are branding the planned rally an 'expression of racism and white supremacy' and have called on believers to speak against it.

'We denounce and repudiate white supremacy as a work of the devil, designed to dehumanize and divide,' said the joint statement from a number of senior leaders including Moore, president, Ethics & Religious Liberty Commission and Frank Page, president of the Southern Baptist Convention.

'We call every follower of Jesus in the state of Tennessee to speak out against white supremacy, in all of its forms and to pray and work for racial unity in our communities. We also pray for those who advocate racist ideologies and those who are thereby deceived, that they may see their error through the light of the Gospel, repent of these hatreds and come to know the peace and love of Christ through redeemed fellowship in the Kingdom of God.'

They added: 'History shows that indifference, by the church, allows such evil to flourish. We must not only declare racism to be wrong, we must oppose specific acts and movements that would degrade and dehumanize our brothers and sisters in Christ.'

It comes after Moore penned an op-ed for the local media outlet The Tennessean, condemning white supremacy as 'backward' and 'devilish'.

In an implicit criticism of Trump's refusal to condemn white nationalists specifically, he wrote: 'If the horror in Charlottesville taught us anything, it's that white nationalism cannot be ignored but must be exposed explicitly' and called on the Church to speak out.

'Racism does what as a Christian I believe the devil exists to do: to kill and to destroy and to exalt the idolatry of self. If we cannot call this what it is, we will sow in cowardice what we will reap in violence,' he wrote.

'American of many different religions, and of no religion at all, should stand together on at least this: that all men are created equal, and endowed by their Creator with certain unalienable rights.

'That should be not just recited, but ensured. White supremacy is sadly too often a part of the American past and the American present, but should have no place in the American future.'