A gay group is protesting over the decision of US television network CBS to show an advert by Focus on the Family during the Super Bowl next Sunday.

Focus on the Family, which says homosexuality “violates” God’s will, is to screen an ad featuring football star Tim Tebow and his mother. Pam Tebow will discuss how she was told to abort her son in 1987.

The Super Bowl is the championship game of the National Football League and is the most watched event on US television.

Women’s groups have also complained about the pro-life message and the Gay and Lesbian Alliance Against Defamation complained that CBS had rejected a 2004 ad from the gay-friendly United Church of Christ which promoted LGBT equality.

At the time, CBS said the United Church of Christ’s ad was “unacceptable for broadcast” as President George Bush had recently proposed a constitutional amendment restricting marriage to heterosexuals.

GLAAD senior director of media programmes Rashad Robinson said in a statement: “CBS spent years denying a platform to an LGBT-inclusive church that wanted to share a message of inclusion with a national audience.

“Now, when it happens to be financially inconvenient for CBS to hold to the standard it had previously imposed, the network’s expediency benefits a virulently anti-gay organisation whose advocacy on these issues is the antithesis of that of the United Church of Christ.”

CBS said this week that it had changed its policies on ads and that the church’s 2004 ad would have been accepted now.

A spokesman told Associated Press this week: “We have for some time moderated our approach to advocacy submissions after it became apparent that our stance did not reflect public sentiment or industry norms.”

Rev. J. Bennett Guess, of the United Church of Christ, said: “CBS’ about-face only underscores the arbitrary way the networks approach these decisions, and the result is a woeful lack of religious diversity in our nation’s media.

“Such flip-flops only lead the public to believe that broadcasters own the airwaves when, in theory at least, they do not.”