DB Breweries has agreed to take down a billboard asking "Would you rather watch porn with your Mum or your sister?", after protesters said it was offensive.

The billboard in Hamilton's CBD advertises a pre-mixed drink made by DB.

It sparked furious debate on talk-back radio this morning after advocacy group Voice Waikato put up a sign in response saying "This is offensive - porn hurts women and children".

Family First NZ said the advertisement showed the Advertising Standards Authority was a "toothless wonder" and stricter controls on billboards were needed.

DB said the drink advertised - Barrel 51 - was an "edgy" new brand following the theme "would you rather".

But it said "one particular" billboard would be taken down after some negative feedback.

"Our aim was never to offend and we have taken this feedback on board and we will take this billboard down," it said.

Family First NZ earlier issued a statement saying the billboard glorified pornography.

"It is offensive to many, and ignores the harm that pornography is doing in our community and the contribution it makes to family breakdown, addiction, aggressive sexual behaviour, sex role stereotyping, and viewing people simply as sexual objects," national director Bob McCroskie said.

Family First has called for a committee to be established to pre-approve billboards.

"Voice Waikato has taken action in a way many families would like to against offensive billboards, because the Advertising Standards Authority is a 'toothless wonder' that is simply being ignored by the advertising industry," Mr McCroskie.

He said the committee should include specialists to advocate for the protection of children and families from offensive billboards.

"Families are sick to death of being confronted with offensive material as they drive along motorways and through city streets."