The Daily Mail got a slim model to try these items on. Illustrating just how tiny they were, the size 8 woman could barely pull the shorts over her thighs. Other garments in size 2 included a pair of skin-tight red trousers with a hip measurement of 31in, compared to the average of 42in.
On a website about eating disorders, a girl said news of the smaller sizing had sent her into a 'state'. She added: 'This means another smaller size I have to fit into. Now I have to buy something to see if I fit.'
Liberal Democrat MP Norman Lamb, a former minister for mental health, said stocking clothes in such small sizes was 'dangerous'.
He added: 'This is totally irresponsible behaviour from Asos. It runs the risk of normalising sizes which are extreme for adults. It sends out a very dangerous signal to teenagers and young women.'
Asos, which is popular with teenage girls and young women, sells a variety of brands as well as its own line of clothing.
Its size 2 items can be found in the company's 'petite' range. Tory MP Bob Blackman claimed idealising such small sizes could lead to young women developing eating disorders.
He said: 'This is unhealthy, leads to unfair pressures and body image problems. I have also been concerned about the impact this has on mental health, leading to eating disorders and examples of self-harm.'
A spokesman for charity Eating Disorder Support said making sizes smaller gave anorexia and bulimia sufferers a new challenge to fixate upon. She said: 'These sizes do not cause the problem. But the very competitive nature of the illness makes small clothes an attractive goal, which certainly does not help recovery.'
Lib Dem MP Christine Jardine said: 'Of course there are young women who are naturally this size, but we must be responsible about how this is portrayed and not promote it as an ideal.' She added: 'We are still far too obsessed with size and should be encouraging our young people to be comfortable with who they are, not running the risk that they feel pressured to conform to an unrealistic or even unhealthy body shape.'
Criticising the retailer on Twitter, one customer wrote: 'Seriously Asos who is a UK size 2? That's a child's sizing isn't it?'
Another said: 'Honestly isn't a 2 just children's size because what fully grown woman is a 2?'
A spokesman for Asos, which was founded in 2000, claimed the company stocked size 2 clothing with an aim to be 'inclusive'.
He said: 'We take an inclusive approach to helping young people look, feel and be their best.
'We believe cultural, physical and individual differences are to be celebrated and so we offer fashion in over 30 different sizes.'
