Former president Jimmy Carter has insisted that Jesus would support gay marriage, less than two weeks after the US legalised same-sex unions.

"I think everybody should have a right to get married, regardless of their sex" Carter explained during an interview with HuffPost Live.

"I don't have any verse in scripture...I believe that Jesus would approve gay marriage, but that's just my own personal belief," he added.

"I think Jesus would encourage any love affair if it was honest and sincere and was not damaging to anyone else, and I don't see that gay marriage damages anyone else."

However, he said he would not be in favour of the government being able to force a local church to perform gay marriages against its will.

Carter, a devout Christian, spoke about the importance of faith during his presidency, as well as in the present day. "It's always been important in my life. I'm a born again Christian...I'm a Baptist, I taught Sunday school the day before yesterday, and I'll be teaching again next Sunday," he said.

"I'm deeply involved in our church, and my faith has been kind of a foundation of my encouragement when I was in trouble or failed on something, and has given me a new opportunity or motivation to reach for greater things in my own life.

"I never really ran into any serious conflicts between my political obligations and my religious faith," he continued, though he said that he did have "a problem with abortion".

"I have a hard time believing that Jesus for instance would approve of abortions unless it was because of rape, or incest or the mother's life was in danger. So I've had that struggle. But my oath of office was to obey the constitution...so I went along with that," he explained.

Speaking of the recent shooting in Charleston, South Carolina, Carter said he was not surprised when the Emmanuel African Methodist Episcopal Church's congregation chose to forgive the man who killed nine of its parishioners. Carter grew up attending an AME church in Georgia.

He said one of most important values of the Christian faith is "total forgiveness".

"Christ said we must forgive people seventy times seven times, so that was not a shock to me to see them do that altruistic, natural response to a terrible tragedy. I was very grieved when it happened, and my hope is that the church will be healed, and it will be even stronger in the future because of the tragedy that has struck those people."

With regard to race relations in the US, Carter said: "we still have a long way to go".