The Christian bakery at the heart of the gay-cake case should not have been found guilty of discrimination, Northern Ireland's Attorney General has told the court.

Ashers Baking Company refused to bake a cake with the slogan "Support Gay Marriage" for Gareth Lee, who is an LGBT activist. The Christian-owned bakery was found guilty of discrimination against Lee by a county court in 2014.

The company has appealed the ruling and a case is ongoing at the region's Court of Appeal.

The case was scheduled to be heard earlier this year but was postponed after a last minute intervention by John Larkin, Northern Ireland's Attorney General.

Larkin was granted permission to take part after he raised concerns that Northern Ireland's equalities legislation could discriminate against those who hold a religious belief. He told the court this case was far wider than the cake in question. "This case is about expression," he said.

He added that if Lee had "been refused some of Ashers excellent chocolate eclairs because he was gay or perceived to be gay then I would be standing on the other side of court".

He added: "But it's not about that, it's about expression and whether it's lawful under Northern Ireland constitutional law for Ashers to be forced...to articulate or express or say a political message which is at variance with their political views and in particular their religious views."

He said Lee's sexual orientation was of "supreme irrelevance" to the bakery.

However a barrister for Lee said the McArthur family, who own Ashers, were not forced to do anything against their beliefs.

"It is no more forced speech than any of the delivery merchants or the post office or any of the companies that printed the numerous hoardings around Belfast and the rest of Northern Ireland for the Assembly elections this week."

One of the three judges presiding over the case asked if the phrase "Support Gay Marriage" could be argued to be blasphemous.

Lee's barrister said it was not blasphemous because the campaign for gay marriage was a civil recognition.

"It's not abusive of religion to say 'support gay marriage'," he added.

"Just because you ice a cake with 'Larne Ladies Football Club' doesn't mean you support them, even if all your staff were arch rivals of Larne Ladies Football Club," he said.

The hearing continues.