A Christian politician says a new law banning homophobia in Switzerland threatens the freedom of speech of Christians.

Sixty-two per cent of Swiss voters agreed to criminalise discrimination on the grounds of sexual orientation in a referendum on Sunday.

The amendment expands existing antidiscrimination legislation which safeguards race, ethnicity and religion to include protection for the LGBTQ community.

Christian evangelical party UDF opposed the amendment, saying it went beyond just outlawing hate. 

UDF MP Samuel Kullmann told Premier the party is concerned for the limitations it could bring to the freedom of speech for Christians. 

He said: "In Finland, a Member of Parliament from the Christian Democrats was questioned by the police numerous times simply for posting a Bible verse on her Twitter account. And she was even questioned for a booklet she wrote 15 years ago about her view on Christian ethics and marriage."

"In almost every country that has passed a similar law, we find examples that show that it's actually much more than what most Christians would understand as hate speech."

Kullmann went on to clarify that the party is in no way condoning hate speech or "being rude to people," but says that in practice, these laws can infringe on the freedom of conscience of Christians.

Under the amended law, homophobic comments made in public would be punishable with up to three years in prison. This includes television broadcasts, social media posts, and discrimination against gay or bisexual people in public venues.