LONDON -- The owners of a Northern Ireland bakery that refused to bake a cake supporting gay marriage said Thursday they would appeal their conviction for discrimination.

The Christian owners of Ashers Baking Company were convicted last week after refusing an order from gay rights activist Gareth Lee. He asked for a cake featuring Sesame Street characters Bert and Ernie and the words "Support Gay Marriage."

Belfast judge Isobel Brownlie ruled that the bakery had discriminated against Lee on grounds of sexual orientation and political beliefs and ordered it to pay 500 pounds ($765) in damages, plus thousands in legal costs.

The judge said the bakery was a business, not a religious organization, and therefore had no legal basis to reject an order based on a customer's sexual orientation or beliefs.

Members of the McArthur family, the bakery's owners, said that "after much careful and prayerful consideration given to legal advice," they had decided to appeal.

"We continue to insist that we have done nothing wrong as we have discriminated against no individual, but rather acted according to what the Bible teaches regarding marriage," they said.

Same-sex marriages were legalized last year in the rest of the United Kingdom, but remain unrecognized in Northern Ireland.