Adverts for Nike and Sky have been banned by the regulator for using “dark pattern” tactics designed to lead consumers to unintentionally spend money.

Nike had advertised a shoe at a low price, causing consumers to click through only to find that it was for a children’s size, while Sky did not make it clear that a free trial for Now TV would automatically renew with a charge unless cancelled.

The Advertising Standards Authority (ASA) said both rulings were part of its wider work investigating “online choice architecture” (OCA).

Concerns around OCA include price transparency, hidden fees and “drip pricing”, as well as fake and misleading reviews.