A bus company based in Cardiff, Wales, has been forced to pull ads on its buses featuring topless models holding signs reading "Ride me all day for £3" after it was accused of sexism.The ads, promoting New Adventure Travel's new cross-city service in Cardiff, only launched at the weekend but the company withdrew the ads on Monday morning after they sparked outrage, which many people vented on Facebook and Twitter - which is where we first spotted the story.Welsh singer Charlotte Church even got involved in wave of social media backlash directed at the company:This is atrocious.@EverydaySexism @NAT_Group can't imagine @charlottechurch would be happy about this atrocious sexism in Cardiff!"- Charlotte Church (@charlottechurch) May 11, 2015.@nat_group HOW AM I SUPPOSED TO EXPLAIN THIS AD TO MY PRIMARY SCHOOL KIDS?? Thanks but no thanks, won't be taking advantage #everydaysexism- Michelle Davis (@michelledavis) May 11, 2015Dear @NAT_Group, I find your new promotion in Cardiff hugely uncomfortable, not to mention objectifying... pic.twitter.com/OPipr7Ovea- Vicky Chandler (@VickyChandler) May 11, 2015A spokeswoman from the Advertising Standards Authority told Business Insider it had received 45 complaints, claiming the depiction of the woman in the ad was offensive. However, it is likely that the ad falls outside the ASA's remit because it ran on the company's own property.The ASA said in an e-mailed statement: "We've received complaints about this ad but we understand that the advertiser will be taking it down within the next 24 hours and has removed its accompanying tweet in response to the concerns it's received. We'll continue to monitor the situation in case further action is needed."New Adventure Travel published this statement via Twitter on Monday:In view of the reaction to our bus advertising today we wish to set out our position:Firstly we have stated that our objectives have been to make catching the bus attractive to the younger generation. We therefore developed an internal advertising campaign featuring males and females to hold boards to promote the cost of our daily tickets.The slogan of 'ride me all day for £3' whilst being a little tongue in cheek was in no way intended to cause offence to either men or women and, if the advert has done so then we apologise unreservedly. There has certainly been no intention to objectify either men or women.Given the volume of negativity received we have decided to remove the pictures from the back of the buses within the next twenty four hours.SEE ALSO: A TV ad for 'the world's slimmest phone' has been banned for objectifying womenJoin the conversation about this story »NOW WATCH: 5 Tricks Advertisers Use To Make You Buy Their Products