The Catholic Church in Scotland has stepped up its opposition to plans to legalise gay marriage by issuing a fresh warning to the Scottish Government.

Former Archbishop of Glasgow Mario Conti has described same-sex marriage as "morally defective" and urged ministers not to equate "homosexual unions with heterosexual marriage" by legislating.

Archbishop Emeritus Conti's latest remarks come as the Scottish Government continues to seek views on its Marriage and Civil Partnership (Scotland) Bill.

In a letter published in the Catholic journal, The Tablet, the Archbishop wrote: "While it is true, certainly within Catholic social teaching, that governments are not required to make all immoral actions illegal, to many it is unhelpful, unnecessary and indeed profoundly unwise for political action to do quite the opposite, namely to attempt through the law, by equating homosexual unions with heterosexual marriage, to render moral what is in itself morally defective."

He went on to say that the Catholic Church's opposition must "surely be worthy of consideration" given its task to "promote the moral well-being of society".

LGBT equality charity the Equality Network has called on the Government to stand firm on its proposed laws.

Tom French, policy co-ordinator for the charity, said: "In a free society, Archbishop Conti is entitled to express his views, however offensive they may be.

"Thankfully, most people in Scotland support same-sex marriage and disagree with the assertion that their gay friends and family members are 'morally defective'.

"The Catholic Church has long campaigned against equal rights for lesbian, gay, bisexual and transgender people, and for Archbishop Conti to imply that same-sex relationships should now be made illegal is evidence of a worrying anti-gay agenda."

In July, the Scottish Government announced plans to legalise same-sex marriage in the country following a consultation which attracted 80,000 responses.

The proposals have already received cross-party support in Holyrood.