Franklin Graham has warned American is in "imminent danger" because of its rejection of God.

The son of famous evangelist Billy Graham has launched a tour of all 50 American states to urge Christians to pray for the political process. The Decision America Tour began in January and Graham says he has "no hope in either the Democratic or Republican party" but "our only hope is in Almighty God".

In a damning piece for Decision Magazine Graham asked whether the "writing was on the wall" for the US.

"Has God decided that our idolatry, immorality and godlessness has become such a stench in His nostrils that we as a people will experience a harsh form of divine judgment?," he wrote.

"Have our iniquities grown so foul and vast that we will reap the bitter harvest of our wickedness and rebellion against Almighty God?"

He continued: "We are a people and nation in imminent danger. We mock God, ridicule His Word and 
His ways, and flaunt gross 
immorality.

"Only Almighty God can deliver us, and it is our fervent prayer as we go across America in the months to come, that He will hear our prayers and heal our land."

Graham is CEO of Samaritan's Purse and the Billy Graham Evangelistic Association. He claimed Christians in America are under "constant, unrelenting assault for our beliefs and practices".

"Never before have I seen such a sharp rift in the moral and spiritual fabric of our country. The Cross of Christ has become the deep divide between a growing segment of our population that no longer fears God and those who follow Christ as Lord and Savior.

"In this secular age, the influence of Biblical principles and values has diminishing impact upon education, government and politics."

Despite his bleak outlook on the spiritual state of America, Graham offered a ray of light to finish.

"I do believe that God is able to restore and heal us if we repent of our sins—personal and corporate—and turn to Him in humility and reverence."

He wrote: "He is our only hope."