Members of the Welsh Assembly are up in arms after a Cardiff film production company used a baby-changing room at the £70 million Senedd building to shoot a sex scene.

Assembly authorities gave Fiction Factory permission to film various scenes at the landmark building last month, including what they thought would be a "conversation scene" in the Senedd's baby-changing facility.

In the event, however, that scene was notable for its non-verbal communication as Lea, a 29-year-old civil servant played by the actress Alys Thomas, entices her older lover, played by Dewi Rhys Williams, into the room for a moment of forbidden passion.

The scene was shot for the S4C Welsh-language series Caerdydd (Cardiff), Wales's answer to Sex and the City. The series follows a group of twenty- and thirty-somethings as they go about their hectic daily lives in Cardiff.

According to the Western Mail, the series launched in 2006 and "immediately attracted attention for its raunchy storylines, graphic scenes of sex and drug-taking and heavy use of English".

Caerdydd is advertised with the tagline: “Love and lust at the cutting edge of capital city life”.

An Assembly spokeswoman said: “Permission was granted to film in the Neuadd area, the corridors of the building and for one scene in the baby-changing room. However, the National Assembly was told that this scene was a conversation scene and was not aware of its full content.The company was allowed to film in good faith.”

An S4C spokeswoman said: “S4C is in contact with Fiction Factory, the producers of Caerdydd, and is looking into the matter.”

Among those complaining is William Graham, a Conservative AM and member of the Assembly Commission which is responsible for running the building. Mr Graham told the Western Mail last night that he expected people to be outraged.

“This is obviously unpleasant and unnecessary," Mr Graham said. “Potentially it’s distressing for people who don’t like the idea of one of the buildings they funded being used in this way.”

Adding that the incident would have implications for further dramas filmed at the Senedd, Mr Graham said: “One doesn’t want censorship but nothing that is controversial or concerning should happen.

“My mother would be outraged – and I think rightly so.”

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