Tweets sent by footballers Wayne Rooney and Jack Wilshere have been banned after a watchdog ruled they were advertisements for sportswear giant Nike.
Rooney tweeted from his official account in January: "My resolution - to start the year as a champion, and finish it as a champion ... £makeitcount gonike.me/makeitcount."
Wilshere wrote at around the same time: "In 2012, I will come back for my club - and be ready for my country. £makeitcount.gonike.me/Makeitcount."
One person complained that both tweets were not obviously identifiable as marketing on behalf of Nike.
Defending the campaign, Nike said Twitter was a more direct channel of communication between two parties than traditional media, adding that the players were only communicating with those who had chosen to follow them and both were well known for being sponsored by Nike.
The company said it therefore believed that Rooney and Wilshere's Twitter followers would not be misled about the relationship between the footballers and Nike.
It believed the players' Twitter feeds made it clear which were personal tweets and which were ads, and the inclusion of the Nike URL combined with the Nike campaign strap line £makeitcount made it sufficiently clear that those tweets were advertisements.
The Advertising Standards Authority (ASA) said it understood both players were required to take part in marketing activities and both were asked to give their own ideas on what to write in their tweets, but that the final content was agreed with the help of a member of the Nike marketing team.
However, the ASA said: "We considered that the Nike reference was not prominent and could be missed, consumers would not have already been aware of Nike's "£makeitcount" campaign and that not all Twitter users would be aware of the footballers' and their teams' sponsorship deal with Nike.
"We considered there was nothing obvious in the tweets to indicate they were Nike marketing communications. In the absence of such an indication, for example £ad, we considered the tweets were not obviously identifiable as Nike marketing communications and therefore concluded they breached the code."
It ruled that the "ads" must no longer appear and told Nike to ensure that its advertising was obviously identifiable as such.