A poster advertising a 50p offer for KFC spicy Zinger chicken drumsticks has been ruled untruthful by the advertising watchdog because the small print clarifying the offer was only 1cm high in a 180 cm poster.

The poster advertising the Zinger chicken drumstick said "to try it just find 50p".

But it was only the small print that made clear that this only applied when a "bucket" or meal was also purchased.

The small print at the bottom of the poster stated: "New spicy Zinger chicken pieces are chicken on the bone. Limited to one piece per transaction with any bucket or meal. 'Meal' is defined as minimum of fries, drink (regular or large in each case) plus one of the following burger, twister or bucket or any items listed on the classics menu. Limited period only. Subject to availability".

KFC told the Advertising Standards Authority that the text was "unambiguous" and the poster had clearly set out the terms and defined the meaning of a "meal" in relation to the offer.

It said the conditions were "printed in clear typeface", which "was big enough to read easily and were sufficiently prominent and unambiguous for a consumer to understand".

The poster, created by advertising agency Bartle Bogle Hegarty, was displayed in 7,000 outlets for two weeks, and point of sale material in the shops further explained the offer to customers.

KFC said that as only three consumers had complained it believed that showed the poster was not misleading.

The ASA considered that referring to the significant condition only in small print was "likely to mislead consumers" about the nature of the offer and that the condition could be seen to contradict the impression created by the headline claim.

It ruled that the poster breached committee of advertising practice code clauses on truthfulness and significant conditions for promotions.

The ASA told KFC to state important conditions for promotions more prominently in future ads.

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