Kerry Katona has been dropped as the face of supermarket chain Iceland following allegations that she took cocaine.

The News Of The World published photographs and video footage of the 28-year-old mother allegedly showing her snorting the class A drug in her home in Wilmslow, Cheshire.

Dropped: Former Atomic Kitten singer Kerry Katona

Iceland said last night that while the company had stood by her during earlier personal difficulties, it was now "impossible" for her to continue in its advertising campaign.

The former Atomic Kitten singer, who has endured a long and public battle with alcohol and drugs, as well as a roller-coaster romantic life, fronted the supermarket's advertising campaigns for four years.

In a statement, Iceland said: "For most of that time, she has been a successful part of our advertising campaigns, but has also been through some tough times in her personal life.

"We have always stood by her, as an example of a normal person and mum who has experienced some of the modern-day culture of fame, and how difficult it can be to deal with.

"However, following the most recent allegations, we feel it is impossible for Kerry to continue to work with us as one of the faces of Iceland advertising.

"In recognition of the relationship we have developed, we will continue to try and help Kerry to ensure she get the most appropriate support, should she require our assistance."

Katona, who had two children with Westlife singer Bryan McFadden and two more with Mark Croft, won the Best Celebrity Mother award in 2004 and 2005, though she was criticised for smoking and drinking while pregnant.

An interview on This Morning last October earned Katona a large measure of notoriety as she slurred and appeared confused, though she later said this was due to medication she was taking for her bipolar disorder.

She has been the subject of several reality TV shows on MTV, most recently Kerry Katona: What's The Problem?, charting her attempt to understand and come to terms with her mental illness.

Losing the six-figure Iceland contract will not help her financial troubles - last August she was declared bankrupt after failing to pay off a £417,000 tax bill and in May this year she told GMTV that she was "skint".

She said the mood swings caused by her bipolar disorder was partly to blame, as she tended to spend "loads of money" when she was on a high.

Iceland uses a number of other celebrities to promote its stores - including Coleen Nolan, singer and star of ITV show Loose Women - and it is not known if Katona will be replaced.