Archbishop weighs into same-sex debate

The leader of Perth's Catholic community has weighed in to the same sex marriage debate, saying those opposed to it shouldn't be labelled homophobic.

Archbishop Timothy Costelloe has written a letter that will be distributed at parishes this weekend outlining the church's position.

"I certainly think people of goodwill can oppose gay marriage without being homophobic - I do hope they can also do so without being labelled homophobic," he told 6PR radio on Friday.

He accepted there were many different types of families, "which is not to say that other situations are devoid of anything good", but insisted traditional marriage was the best.

"In an ideal world, we should be doing everything we can to ensure that children have the chance to be brought up in a loving, stable environment with their natural mum and dad," he said.

"Traditional marriage has served our society very well. It's the foundation of marriage and family is the foundation of our society."