'The Civil Partnership Act (CPA) came into force on 5th December 2005. It enables same-sex couples to register their partnerships.
It creates a new legal relationship - that of a civil partnership - but it is NOT a marriage.

During the genesis of CPA 2004, some commentators suggested that, far from alleviating discrimination against the gay and lesbian community, it would solidify and legitimize discrimination.
The complaint was that the law does not place civil partnerships on an equal footing with heterosexual marriage and that creating civil partnerships reinforces and perpetuates discrimination.'

Source: New Law Journal

I agree with Ruth's sentiments; I was personally married in a civil ceremony because I am not a believer in any Christian religion and religion didn't, and shouldn't, play any part in a civil union IMO