My view on marriage hasn't changed: PM

Prime Minister Tony Abbott says he hasn't changed his mind on gay marriage and the historic ruling by the US Supreme Court is a matter for the Americans.

"What happens in the United States is obviously a matter for the United States, just as what happened in Ireland a few weeks ago is a matter for the Irish," he told reporters in Melbourne.

"Obviously there is a community debate going on, I have views on this subject which are pretty well known and they haven't changed."