The garments are advertised on the store's website, which says: "Introducing La Senza's latest collection – La Senza Girl, why should grown-ups have all the fun?"

The site, which boasts that its adult collection is "sexy, sensual, flirty and romantic", claims the underwear is intended to offer young girls "coverage" before they are ready for a training bra.

But politicians, children's charities and campaigners have hit out angrily at the chain, saying it is putting children at risk and encouraging teenage pregnancy.

Claude Knights, director of child protection charity Kidscape, said: "There is no doubt La Senza's brand is based on adult lingerie and is not for children.

"The worry for us is always that we create children as sexual beings without them realising it, which only creates further problems in society.

"These young children are being offered a specific adult look without them fully understanding the consequences.

"I would hope most parents would be critical to see it for what it is."

David Davies, Conservative MP for Monmouth, claimed La Senza was "willing to make profits at the expense of public morality".

"We currently have the highest level of teenage pregnancy in the whole of Europe and the last thing we need is to encourage further sexual experimentation in young children," he said.

"If you sexualise children at a young age, they tend to have children at a young age, often in unstable circumstances where they are unable to take care of the child in a responsible way.

"The state – and ultimately the taxpayer – are having to pay to bring up tens of thousands of these children. We should all resent La Senza for provoking this trend."

La Senza, which has been described as an "Agent Provocateur for the masses", has 176 stores in the UK. The girls' lingerie range was introduced into 20 of its shops last Wednesday.

The store is the latest to be criticised for sexualising young girls.

Asda was forced to remove pink and black lace lingerie, including a push-up bra, which had been marketed to girls as young as nine.

Children's groups also called for a boycott of a Little Miss Naughty range sold by Bhs, which included padded bras. And WH Smith provoked anger after selling a Playboy stationery range to schoolgirls.

The National Society for the Prevention of Cruelty to Children called for retailers to be more responsible about their products.

Chris Cloke, the charity's head of child protection awareness, said: "Retailers must ensure they are not irresponsibly marketing adult-style clothing to children."

But a spokesman for La Senza said: "I absolutely refute any suggestion that we are sexualising young children. This range is in just 20 stores and is supposed to be fun – we're not Ann Summers."