Former Relate counsellor Gary McFarlane, who was sacked after refusing to give sex therapy to same-sex couples, said the judgment by the European Court of Human Rights against him was "regrettable".
Speaking in central London, he said he would appeal the decision while continuing to counsel same-sex couples in other aspects of their lives.
The ECHR's ruling found against Mr McFarlane on the grounds that he took on the role at Relate in the knowledge that clients could not be divided up in accordance with their sexual orientation.
It concluded the company's action was designed to enable it to provide a service without discrimination.
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