A bishop in the state of Wisconsin has spoken out urging voters to choose only candidates who are opposed to equal marriage and abortion, saying that those in favour of such policies were “intrinsically evil”.

Bishop David Ricken, the leader of the Catholic Diocese of Green Bay, wrote a letter to parishioners dated 24 October, in which he said that voting for candidates who support abortion or equal marriage would “put your own soul in jeopardy,” the Green Bay Press Gazette reported.

He also said that the church had a responsibility to “speak out regarding moral issues, especially on those issues that impact the ‘common good.’” The letter continued:

“A well-formed Christian conscience does not permit one to vote for a political program that contradicts fundamental contents of faith and morals.”

The letter does not name any candidates, or any political party in particular, but simply suggests that voting for someone supporting equal marriage or abortion would be the wrong choice, it said:

“Some candidates and one party have even chosen some of these as their party’s or their personal political platform. To vote for someone in favor of these positions means that you could be morally ‘complicit’ with these choices which are intrinsically evil. This could put your own soul in jeopardy.”

President Barack Obama confirmed his support for equal marriage back in May, and the Democratic Party supports unrestricted abortion rights for women.

Mitt Romney opposes both equal marriage and abortion rights. He was recently accused of deliberately trying to make it harder for same-sex couples to register the birth details of their children during his time as governor of Massachusetts.

On Sunday, the New York Times announced its endorsement of Obama for the presidential election, citing his support of same-sex marriage as one of its main reasons.

Ricken’s diocese reportedly has 304,614 members spread across 16 counties, and Catholics make up 25% of the population of Wisconsin, according to the Association of Statisticians of American Religious Bodies’ 2010 US Religion Census.