A bill that aims to protect pastors who refuse to officiate in same-sex weddings has failed to gain the approval of lawmakers in Louisiana.

House Bill 597 states that a legally recognised church or faith "may not be required by the state to solemnize a marriage, nor provide access to facilities, services, accommodations, goods, or privileges of the church, faith, or religious organization for a purpose related to the solemnization, formation, or celebration of the marriage, if the actions would be contrary to church doctrine, practice or in violation of the religious beliefs and principles of the clergy, church, or religious organization."

State Rep. Mike Johnson, who introduced the bill, said the purpose of the measure "was to prevent the state from taking any adverse action against a member of the clergy, church or religious organization merely for abiding by their sincerely held religious beliefs," according to the Times-Picayune.

He said the bill is needed after the U.S. Supreme Court legalised same-sex marriage in the country last year.

Supporters of the bill include the Family Forum and a church clergy in Baton Rouge who testified for the bill.

Johnson warned pastors who attended the committee hearing that they should expect the American Civil Liberties Union (ACLU) and Human Rights Coalition to come after them if they decline to perform gay weddings.

ACLU Louisiana Director Marjorie Esman disputed this, saying, "we will always defend the rights of a clergy person not to do something against their faith."

Stephen Perry, CEO of the New Orleans Convention and Visitors Bureau, said if the bill is passed, the state could suffer millions of dollars in losses in the tourism sector.

"We believe we have today a potentially very damaging bill that takes a different twist on the law we have on the books now. We are in negotiations with corporations and associations all over the United States who are watching this and are very concerned," he said.

Two Democrats opposed the bill, claiming it would also allow pastors to refuse officiating the wedding of interracial couples. Johnson denied this.

"I'm not aware of any religious tradition in this state that is opposed to interracial marriage. I certainly don't know any clergy who would refuse to do that," he said.