Three television adverts for electronic cigarettes have been banned, just weeks after the rules were changed so people could be shown using them.
Two of the adverts featured a woman exhaling vapour which, according to the Advertising Standards Authority (ASA), appeared to glamourise the smoking of tobacco products.
Another was said to be encouraging non-smokers to take up e-cigarettes.
The ASA had received more than 200 complaints about the adverts.
Since November, manufacturers have been allowed to advertise the use of electronic cigarettes on TV, as long as they do not promote tobacco or target non-smokers or young people.
Critics of so-called e-cigarettes argue that the devices may encourage people to see smoking as acceptable.
Two adverts for Must Have, which trades as VIP Electronic Cigarettes, showed a woman exhaling vapour - known as vaping - as a voiceover recommended "the great taste of VIP".
The ASA received 199 complaints, including some from organisations such as Ash (Action on Smoking and Health), the Association of Directors of Public Health UK (ADPH) and the British Medical Association (BMA).
Must Have argued that the adverts stated the product was an e-cigarette, which they said made it clear that no tobacco was being promoted.
But although the advert did not mention tobacco, the ASA ruled that close-ups of the woman exhaling drew particular attention to the vapour.
The ASA said: "We considered that the manner in which the vapour was exhaled and the heightened focus on this action created a strong association with traditional tobacco smoking.
"Because the ads presented it, as the central focus of the ads, in a sultry and glamorous way, we considered that they indirectly promoted the use of tobacco products."
In a separate ruling, the ASA banned a Vape Nation advert for encouraging ex-smokers to use e-cigarettes.
The clip promoting KiK e-cigarettes featured a group of adults using and discussing the devices, with one man saying: "I used to smoke normal cigarettes, but after I quit, I tried these. I actually prefer them."
The ASA received seven complaints from viewers who argued the advert would encourage non-smokers, and particularly former smokers, to use them.
Vape Nation denied this, arguing the advert was aimed at current smokers.
But the ASA said: "We considered that the man's statement could encourage non-smokers to take up using e-cigarettes and we therefore concluded the ad was irresponsible."
It ruled all three adverts must not appear again in their current form.